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c++variablesincludeintlvalue

Expression must be an L value

I'm trying to make a formula that can identify a right triangle. I'm having some problems with "a" and the = sign.

Error 1: '='; left operand must be l-value.
Error 2: "a". Expression must be a modifiable lvalue.

Any help? 

#include "stdafx.h"
#include <iostream>
#include <cstdio>
#include <cmath>

 using namespace std; 


int main()
{
    int a; 
    int b;
    int c;
    cout << "Input value for A." << endl; 
    cin >> a; 
    cout << "Input value for B. " << endl; 
    cin >> b; 
    cout << "Input value for C. " << endl; 
    cin >> c; 

    a ^ 2 + b ^ 2 = c ^ 2; 
    return 0;
}
Solution

  • ^ operator is used to get bit-wise XOR in C++. You should do it in following way:

    instead of a ^ 2 + b ^ 2 = c ^ 2 statement, write a block like:

        if(pow(c, 2) == pow(a, 2) + pow(b, 2))
        std :: cout << "true";
    else
        std :: cout << "false";