2024-3-18
This commit is contained in:
282
Chapter3/ValExpression/Expresion.cpp
Normal file
282
Chapter3/ValExpression/Expresion.cpp
Normal file
@@ -0,0 +1,282 @@
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#include<iostream> //cout,cin
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using namespace std;
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#include"SqStack.h"
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char pause;
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char Precede(char t1, char t2) //算符的优先级比较
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{
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char f;
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switch (t2)
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{
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case '+':
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case '-':if (t1 == '(' || t1 == '=')
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f = '<';
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else
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f = '>';
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break;
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case '*':
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case '/':if (t1 == '*' || t1 == '/' || t1 == ')')
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f = '>';
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else
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f = '<';
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break;
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case '(':if (t1 == ')')
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{
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cout << "ERROR1" << endl;
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exit(0);
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}
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else
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f = '<';
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break;
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case ')':switch (t1)
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{
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case '(':f = '=';
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break;
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case '=':cout << "ERROR2" << endl;
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exit(0);
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default: f = '>';
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}
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break;
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case '=':switch (t1)
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{
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case '=':f = '=';
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break;
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case '(':cout << "ERROR2" << endl;
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exit(0);
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default: f = '>';
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}
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}
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return f;
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}
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bool In(char ch) // 判断 ch 是否为运算符
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{
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switch (ch)
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{
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case'+':
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case'-':
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case'*':
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case'/':
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case'(':
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case')':
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case'=':return true;
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default:return false;
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}
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}
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float Operate(float a, char theta, float b)
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{ // 实施一次运算
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float ch;
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switch (theta)
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{
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case'+':ch = a + b;
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break;
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case'-':ch = a - b;
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break;
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case'*':ch = a * b;
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break;
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case'/':ch = a / b;
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}
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return ch;
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}
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//算法3.12
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float Val_Exp(char* exp) // 中缀表达式求值。
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{
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SqStack<char> OP; // 运算符栈
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SqStack<float> OD; // 运算数栈
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InitStack(OP, 30);
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InitStack(OD, 30);
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char theta;
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float a, b, result;
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char ch, x; // 存放由键盘接收的字符
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char z[6]; // 存放符点数字符串
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int i;
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Push(OP, '='); // # 是表达式结束标志
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ch = *exp++;
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GetTop(OP, x);
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while (ch != '=' || x != '=')
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{
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if (ch >= '0' && ch <= '9' || ch == '.') // ch 是操作数
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{
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i = 0;
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do
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{
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z[i] = ch;
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i++;
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ch = *exp++;
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} while (ch >= '0' && ch <= '9' || ch == '.');
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z[i] = '\0';
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result = atof(z); // 将字符串数组转为符点型存于result
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Push(OD, result);
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}
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else if (In(ch)) // 是7种运算符之一
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switch (Precede(x, ch))
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{
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case'<':Push(OP, ch); // 栈顶元素优先权低
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ch = *exp++;
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break;
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case'=':Pop(OP, x); // 脱括号并接收下一字符
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ch = *exp++;
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break;
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case'>':Pop(OP, theta); // 退栈并将运算结果入栈
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Pop(OD, b);
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Pop(OD, a);
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Push(OD, Operate(a, theta, b));
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}
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else // ch是非法字符
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{
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cout << "ERROR3" << endl;;
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exit(0);
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}
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GetTop(OP, x);
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}
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GetTop(OD, result);
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DestroyStack(OP);
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DestroyStack(OD);
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return result;
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}
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void CreatePostExp(char* exp, char*& postexp) // 由中缀式求后缀式
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{
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char ch, x;
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int i = 0;
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SqStack<char> OP;
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InitStack(OP, 30);
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Push(OP, '='); // # 是表达式结束标志
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cout << "中缀表达式：" << exp << endl;
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ch = *exp++;
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while (ch)
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{
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if ((ch >= '0' && ch <= '9') || ch == '.')
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{
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postexp[i++] = ch;
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ch = *exp++;
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}
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if (In(ch)) // 是7种运算符之一
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{
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postexp[i++] = ' ';
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GetTop(OP, x);
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switch (Precede(x, ch))
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{
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case'<':Push(OP, ch); // 栈顶元素优先权低
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ch = *exp++;
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break;
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case'=':Pop(OP, x); // 脱括号并接收下一字符
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ch = *exp++;
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break;
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case'>':
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Pop(OP, postexp[i++]); // 运算符出栈输出
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break;
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}
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}
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postexp[i] = '\0';
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}//while
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cout << "\n后缀表达式为:" << postexp << endl;
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DestroyStack(OP);
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}
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//算法3.13
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float Val_PostExp(char* postexp) // 后缀表达式求值
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{
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int i;
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char z[6];
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float result = 0, d = 0, a, b;
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char ch;
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SqStack<float> OD;
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InitStack(OD, 30);
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ch = *postexp++;
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while (ch != '\0')
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{
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if (ch >= '0' && ch <= '9' || ch == '.') // ch为操作数符号
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{
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i = 0;
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do
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{
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z[i++] = ch;
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ch = *postexp++; // 取下一个操作数符号
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} while (ch >= '0' && ch <= '9' || ch == '.');
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z[i] = '\0';
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d = atof(z); // 将字符串数组转为符点型存于result
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Push(OD, d); // 操作数进栈
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}
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if (In(ch)) // ch为运算符
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{
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Pop(OD, a);
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Pop(OD, b);
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Push(OD, Operate(b, ch, a));
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ch = *postexp++;
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}
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ch = *postexp++;
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}
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Pop(OD, result);
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DestroyStack(OD);
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return result;
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}
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//主函数
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void main()
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{
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//int i;
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char exp[20] = "(2.2+5)+4*(5-3.1)=";
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char* postexp;
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postexp = new char[30];
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*postexp = '\0';
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float v;
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system("cls"); // 清屏
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cout << "\n缺省表达式：" << exp;
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cout << endl;
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int choice;
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do
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{ // 显示主菜单
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cout << endl;
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cout << "1-创建表达式\n";
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cout << "2-表达式求值\n";
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cout << "3-求后缀表达式\n";
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cout << "4-后缀表达式求值\n";
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cout << "5-显示表达式\n";
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cout << "0-退出\n";
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cout << "输入功能选项（1~5，0 退出）:\n";
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cin >> choice;
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switch (choice)
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{
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case 1: // 创建表达式
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cout << "\n请输入表达式，以=结束" << endl;
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cin >> exp;
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break;
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case 2: // 表达式求值
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v = Val_Exp(exp);
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cout << exp;
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cout << v << endl;
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break;
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case 3: // 求后缀表达式
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CreatePostExp(exp, postexp);
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break;
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case 4: // 后缀表达式求值
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v = Val_PostExp(postexp);
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cout << '\n' << postexp << "=" << v << endl;
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break;
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case 5: // 显示表达式
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cout << endl;
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cout << "\n已创建的表达式为：";
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cout << exp << endl;
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if (strlen(postexp))
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{
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cout << "\n后缀表达式为：";
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cout << postexp << endl;
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}
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break;
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case 0: // 退出
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cout << "\n结束运行，Bye-Bye!" << endl;
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break;
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default://
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cout << "\n无效选择!\n";
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break;
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}
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} while (choice != 0);
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}//end main
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89
Chapter3/ValExpression/SqStack.h
Normal file
89
Chapter3/ValExpression/SqStack.h
Normal file
@@ -0,0 +1,89 @@
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template <class DT>
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struct SqStack // 顺序栈
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{
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DT* base; // 栈首址
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int top; // 栈顶指针
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int stacksize; // 栈容量
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};
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//基本操作的实现
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//【算法3.1】 // 初始化栈
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template <class DT>
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void InitStack(SqStack<DT>& S, int m)
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{
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S.base = new DT[m]; // 申请栈空间
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if (S.base == NULL) // 申请失败，退出
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{
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cout << "未创建成功！";
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exit(1);
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}
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S.top = -1; // 设置空栈属性
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S.stacksize = m;
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}
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//算法3.2】 // 销毁栈
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template <class DT>
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void DestroyStack(SqStack<DT>& S)
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{
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delete[] S.base; // 释放栈空间
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S.top = -1;
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S.stacksize = 0; // 设置栈属性
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}
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//【算法3.3】 // 入栈
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||||
template<class DT>
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||||
bool Push(SqStack<DT>& S, DT e)
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||||
{
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||||
if (S.top == S.stacksize - 1) // 栈满，不能入栈
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||||
return false; // 返回false
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||||
S.top++;
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||||
S.base[S.top] = e;
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||||
return true; // 入栈成功，返回true
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||||
}
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||||
|
||||
//【算法3.4】 // 出栈
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||||
template<class DT>
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||||
bool Pop(SqStack<DT>& S, DT& e)
|
||||
{
|
||||
if (S.top == -1) // 栈空
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||||
return false; // 返回false
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||||
e = S.base[S.top]; // 取栈顶元素
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||||
S.top--; // 栈顶指针下移
|
||||
return true; // 出栈成功，返回true
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||||
}
|
||||
|
||||
|
||||
//【算法3.5】 // 获取栈顶元素
|
||||
template<class DT>
|
||||
bool GetTop(SqStack<DT> S, DT& e)
|
||||
{
|
||||
if (S.top == -1) // 栈空
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||||
return false; // 返回false
|
||||
e = S.base[S.top]; // 栈非空，取栈顶元素
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||||
return true; // 返回true
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||||
}
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||||
|
||||
// 测栈空
|
||||
template<class DT>
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||||
bool StackEmpty(SqStack<DT> S)
|
||||
{
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||||
if (S.top == -1) // 空栈，返回true
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||||
return true;
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||||
else // 空栈，返回false
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||||
return false;
|
||||
}
|
||||
|
||||
//显示栈内容
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||||
template<class DT>
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||||
void DispStack(SqStack<DT> S)
|
||||
{
|
||||
int i = S.top;
|
||||
while (i >= 0)
|
||||
{
|
||||
cout << S.base[i--] << "\t";
|
||||
}
|
||||
cout << endl;
|
||||
}
|
||||
|
||||
138
Chapter3/ValExpression/ValExpression.vcxproj
Normal file
138
Chapter3/ValExpression/ValExpression.vcxproj
Normal file
@@ -0,0 +1,138 @@
|
||||
<?xml version="1.0" encoding="utf-8"?>
|
||||
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
|
||||
<ItemGroup Label="ProjectConfigurations">
|
||||
<ProjectConfiguration Include="Debug|Win32">
|
||||
<Configuration>Debug</Configuration>
|
||||
<Platform>Win32</Platform>
|
||||
</ProjectConfiguration>
|
||||
<ProjectConfiguration Include="Release|Win32">
|
||||
<Configuration>Release</Configuration>
|
||||
<Platform>Win32</Platform>
|
||||
</ProjectConfiguration>
|
||||
<ProjectConfiguration Include="Debug|x64">
|
||||
<Configuration>Debug</Configuration>
|
||||
<Platform>x64</Platform>
|
||||
</ProjectConfiguration>
|
||||
<ProjectConfiguration Include="Release|x64">
|
||||
<Configuration>Release</Configuration>
|
||||
<Platform>x64</Platform>
|
||||
</ProjectConfiguration>
|
||||
</ItemGroup>
|
||||
<PropertyGroup Label="Globals">
|
||||
<VCProjectVersion>17.0</VCProjectVersion>
|
||||
<Keyword>Win32Proj</Keyword>
|
||||
<ProjectGuid>{85ff5098-d9c7-4d2e-b248-4c3e402ad373}</ProjectGuid>
|
||||
<RootNamespace>ValExpression</RootNamespace>
|
||||
<WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
|
||||
</PropertyGroup>
|
||||
<Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
|
||||
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
|
||||
<ConfigurationType>Application</ConfigurationType>
|
||||
<UseDebugLibraries>true</UseDebugLibraries>
|
||||
<PlatformToolset>v143</PlatformToolset>
|
||||
<CharacterSet>Unicode</CharacterSet>
|
||||
</PropertyGroup>
|
||||
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
|
||||
<ConfigurationType>Application</ConfigurationType>
|
||||
<UseDebugLibraries>false</UseDebugLibraries>
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<PlatformToolset>v143</PlatformToolset>
|
||||
<WholeProgramOptimization>true</WholeProgramOptimization>
|
||||
<CharacterSet>Unicode</CharacterSet>
|
||||
</PropertyGroup>
|
||||
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="Configuration">
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<ConfigurationType>Application</ConfigurationType>
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<UseDebugLibraries>true</UseDebugLibraries>
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<PlatformToolset>v143</PlatformToolset>
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<CharacterSet>Unicode</CharacterSet>
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</PropertyGroup>
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<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="Configuration">
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<ConfigurationType>Application</ConfigurationType>
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<UseDebugLibraries>false</UseDebugLibraries>
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<PlatformToolset>v143</PlatformToolset>
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<WholeProgramOptimization>true</WholeProgramOptimization>
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<CharacterSet>Unicode</CharacterSet>
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</PropertyGroup>
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||||
<Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
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||||
<ImportGroup Label="ExtensionSettings">
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||||
</ImportGroup>
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<ImportGroup Label="Shared">
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||||
</ImportGroup>
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||||
<ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
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||||
<Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
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||||
</ImportGroup>
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<ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
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||||
<Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
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||||
</ImportGroup>
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<ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
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<Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
|
||||
</ImportGroup>
|
||||
<ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
|
||||
<Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
|
||||
</ImportGroup>
|
||||
<PropertyGroup Label="UserMacros" />
|
||||
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
|
||||
<ClCompile>
|
||||
<WarningLevel>Level3</WarningLevel>
|
||||
<SDLCheck>true</SDLCheck>
|
||||
<PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
|
||||
<ConformanceMode>true</ConformanceMode>
|
||||
</ClCompile>
|
||||
<Link>
|
||||
<SubSystem>Console</SubSystem>
|
||||
<GenerateDebugInformation>true</GenerateDebugInformation>
|
||||
</Link>
|
||||
</ItemDefinitionGroup>
|
||||
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
|
||||
<ClCompile>
|
||||
<WarningLevel>Level3</WarningLevel>
|
||||
<FunctionLevelLinking>true</FunctionLevelLinking>
|
||||
<IntrinsicFunctions>true</IntrinsicFunctions>
|
||||
<SDLCheck>true</SDLCheck>
|
||||
<PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
|
||||
<ConformanceMode>true</ConformanceMode>
|
||||
</ClCompile>
|
||||
<Link>
|
||||
<SubSystem>Console</SubSystem>
|
||||
<EnableCOMDATFolding>true</EnableCOMDATFolding>
|
||||
<OptimizeReferences>true</OptimizeReferences>
|
||||
<GenerateDebugInformation>true</GenerateDebugInformation>
|
||||
</Link>
|
||||
</ItemDefinitionGroup>
|
||||
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
|
||||
<ClCompile>
|
||||
<WarningLevel>Level3</WarningLevel>
|
||||
<SDLCheck>true</SDLCheck>
|
||||
<PreprocessorDefinitions>_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
|
||||
<ConformanceMode>true</ConformanceMode>
|
||||
</ClCompile>
|
||||
<Link>
|
||||
<SubSystem>Console</SubSystem>
|
||||
<GenerateDebugInformation>true</GenerateDebugInformation>
|
||||
</Link>
|
||||
</ItemDefinitionGroup>
|
||||
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
|
||||
<ClCompile>
|
||||
<WarningLevel>Level3</WarningLevel>
|
||||
<FunctionLevelLinking>true</FunctionLevelLinking>
|
||||
<IntrinsicFunctions>true</IntrinsicFunctions>
|
||||
<SDLCheck>true</SDLCheck>
|
||||
<PreprocessorDefinitions>NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
|
||||
<ConformanceMode>true</ConformanceMode>
|
||||
</ClCompile>
|
||||
<Link>
|
||||
<SubSystem>Console</SubSystem>
|
||||
<EnableCOMDATFolding>true</EnableCOMDATFolding>
|
||||
<OptimizeReferences>true</OptimizeReferences>
|
||||
<GenerateDebugInformation>true</GenerateDebugInformation>
|
||||
</Link>
|
||||
</ItemDefinitionGroup>
|
||||
<ItemGroup>
|
||||
<ClInclude Include="SqStack.h" />
|
||||
</ItemGroup>
|
||||
<ItemGroup>
|
||||
<ClCompile Include="Expresion.cpp" />
|
||||
</ItemGroup>
|
||||
<Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
|
||||
<ImportGroup Label="ExtensionTargets">
|
||||
</ImportGroup>
|
||||
</Project>
|
||||
27
Chapter3/ValExpression/ValExpression.vcxproj.filters
Normal file
27
Chapter3/ValExpression/ValExpression.vcxproj.filters
Normal file
@@ -0,0 +1,27 @@
|
||||
<?xml version="1.0" encoding="utf-8"?>
|
||||
<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
|
||||
<ItemGroup>
|
||||
<Filter Include="源文件">
|
||||
<UniqueIdentifier>{4FC737F1-C7A5-4376-A066-2A32D752A2FF}</UniqueIdentifier>
|
||||
<Extensions>cpp;c;cc;cxx;c++;cppm;ixx;def;odl;idl;hpj;bat;asm;asmx</Extensions>
|
||||
</Filter>
|
||||
<Filter Include="头文件">
|
||||
<UniqueIdentifier>{93995380-89BD-4b04-88EB-625FBE52EBFB}</UniqueIdentifier>
|
||||
<Extensions>h;hh;hpp;hxx;h++;hm;inl;inc;ipp;xsd</Extensions>
|
||||
</Filter>
|
||||
<Filter Include="资源文件">
|
||||
<UniqueIdentifier>{67DA6AB6-F800-4c08-8B7A-83BB121AAD01}</UniqueIdentifier>
|
||||
<Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav;mfcribbon-ms</Extensions>
|
||||
</Filter>
|
||||
</ItemGroup>
|
||||
<ItemGroup>
|
||||
<ClInclude Include="SqStack.h">
|
||||
<Filter>头文件</Filter>
|
||||
</ClInclude>
|
||||
</ItemGroup>
|
||||
<ItemGroup>
|
||||
<ClCompile Include="Expresion.cpp">
|
||||
<Filter>源文件</Filter>
|
||||
</ClCompile>
|
||||
</ItemGroup>
|
||||
</Project>
|
||||
Reference in New Issue
Block a user