c++ - C++中的字符比较

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我正在尝试为基本计算器编写简单的代码，但是由于我对这种laungauge并不陌生，所以我无法调试此错误。

我收到此错误

Compiling failed with exitcode 1, compiler output:
prog.cpp: In function 'int main()':
prog.cpp:7:13: warning: comparison with string literal results in unspecified behavior [-Waddress]
     if(ch== "*"){
             ^~~
prog.cpp:7:13: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
prog.cpp:11:20: warning: comparison with string literal results in unspecified behavior [-Waddress]
     } else if(ch== "/"){
                    ^~~
prog.cpp:11:20: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
prog.cpp:15:20: warning: comparison with string literal results in unspecified behavior [-Waddress]
     } else if(ch== "+"){
                    ^~~
prog.cpp:15:20: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
prog.cpp:19:20: warning: comparison with string literal results in unspecified behavior [-Waddress]
     } else if(ch== "-"){
                    ^~~
prog.cpp:19:20: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
prog.cpp:23:20: warning: comparison with string literal results in unspecified behavior [-Waddress]
     } else if(ch== "%"){
                    ^~~
prog.cpp:23:20: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]

码：

#include<iostream> 
using namespace std;
int main() {
    char ch;
    cin>>ch;
    if(ch== "*"){
        int a,b;
        cin>>a>>b;
        cout<<(a*b)<<endl;
    } else if(ch== "/"){
        int a,b;
        cin>>a>>b;
        cout<<(a/b)<<endl;
    } else if(ch== "+"){
        int a,b;
        cin>>a>>b;
        cout<<(a+b)<<endl;
    } else if(ch== "-"){
        int a,b;
        cin>>a>>b;
        cout<<(a-b)<<endl;
    } else if(ch== "%"){
        int a,b;
        cin>>a>>b;
        cout<<(a%b)<<endl;
    }
    return 0;
}

最佳答案

char用单引号声明；双引号用于字符串文字。

做这个：

if(ch== '*'){ // notice single quote

在所有比较中

关于c++ - C++中的字符比较，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/59336832/

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