我正在尝试从 txt 文件中读取后缀表达式并对其进行评估，输入为 10 5 *，输出应为 50，但它只读取 10 和 5，他无法读取操作符，也没有 ascii 代码，有什么帮助吗？这是我的代码
#include <iostream>
#include <iomanip>
#include <fstream>
#include<stdio.h>
#include<ctype.h>
#include<stdlib.h>
using namespace std;
#define SIZE 40
int stack[SIZE];
int top=-1;
void push(int n)
{
if(top==SIZE-1)
{
printf("Stack is full\n");
return;
}
else
{
top=top+1;
stack[top]=n;
printf("Pushed element is %d\n",n);
system("pause");
}
}
int pop()
{
int n;
if(top==-1)
{
printf("Stack is empty\n");
system("pause");
return 0;
}
else
{
n=stack[top];
top=top-1;
return(n);
}
}
int main()
{
int str[50],ch;
int i=0;
int n,op1,op2;
ifstream inFile;
ch=str[i];
inFile.open("D:\\me.txt");
if (!inFile)
{
printf( "Unable to open file");
system("pause");
exit(1); // terminate with error
}
while (inFile >> ch)
{
if(ch=='+' || ch=='-' || ch=='*' || ch=='/' || ch=='%' || ch=='^' )
{
op1=pop();
op2=pop();
if (op1<op2)
{
n=op1;
op1=op2;
op2=n;
}
if(ch=='+')
n=op1+op2;
else if(ch=='-')
n=op1-op2;
else if(ch=='*')
n=op1*op2;
else if(ch=='/')
n=op1/op2;
else if(ch=='%')
n=op1%op2;
else if(ch=='^')
n=op1^op2;
else
{
printf("The operator is not identified\n");
system("pause");
exit(0);
}
printf("n=%d\n",n);
system("pause");
push(n);
}
else
{
n=ch;
push(n);
}
ch=str[++i];
}
inFile.close();
printf("The value of the arithmetic expression is=%d\n",pop());
system("pause");
return 0;
}