c++ - 变量 'equation' 周围的堆栈已损坏

Question

我正在尝试用 VC++ 制作一个计算器，即使它运行了，它也一直在读取我没有告诉它的内存，而且我不知道如何让它停止。

#include <iostream>
#include <ctype.h>

int main(){

char equation[4];
equation[3] = '\0'; //string terminator
int result;
bool wantsToContinue = true;
char yesOrNo;

equationPrompt:
std::cout << "Enter Equation: ";
std::cin >> equation;

while(wantsToContinue){

    switch(equation[1]){
    case '+':
        result = int(equation[0]) + int(equation[2]);
        break;
    case '-':
        result = int(equation[0]) - int(equation[2]);
        break;
    case '*':
        result = int(equation[0]) * int(equation[2]);
        break;
    case '/':
        result = int(equation[0]) / int(equation[2]);
        break;
    }

std::cout << std::endl << "Your answer is " << result << std::endl;
exitPrompt:
std::cout << "Exit? Y/N: ";
std::cin >> yesOrNo;

if(tolower(yesOrNo) == 'n'){
    wantsToContinue = true;
    goto equationPrompt;
}
else if (tolower(yesOrNo) == 'y')
    wantsToContinue = false;
else{
    std::cout << std::endl << "Unknown response." << std::endl;
    goto exitPrompt;
}
}
return 0;
}

Answer 1

您可以通过不编写 C 和 C++ 的神秘弗兰肯斯坦语言组合来阻止它，而是使用真正的 C++ 字符串类型:

#include <string>
#include <istream>
#include <iostream>


int main()
{
  std::string equation;
  std::cin >> equation;

  // now equation[0] is the first character
}

注意 int(equation[0]) 几乎可以保证不是你想的那样。您想要的是 int x = std::atoi(equation[0]); 或 std::strtol() 之类的东西，但这仅适用于单个数字。可能更简单的只是流式传输到一个整数，它执行一个实际的文本到整数的转换:

int x, y;
std::string operand;

std::cin >> x >> operand >> y;