#include<iostream>

using namespace std;

int main()
{

    char u[10];
    cout<<"Enter shape name ";
    cin>>u;
    if(u=="tri")
    {cout<<"everything is fine";}
    else{cout<<"Not fine";}
    return 0;
}

CodePudding user response：

You are comparing a Char with a String. You might want to rewrite it to this

int main(){
string u;
cout<<"Enter shape name ";
cin>>u;
if(u=="tri")
{cout<<"everything is fine";}
else{cout<<"Not fine";}
return 0;}

CodePudding user response：

The problem is that you're comparing two pointers instead of comparing two strings as explained below.

When your wrote:

if(u=="tri") //here both u and "tri" decay to pointers
{
}

In the above statement, u has type char[10] and it decays to a char* while the string literal "tri" has type const char[4] and it decays to a const char*, due to type decay. This means that you're comparing two pointers instead of comparing the contents of the two strings.

To avoid this problem you should use std::string as shown below:

int main()
{
    std::string u;  //used std::string
    cout<<"Enter shape name ";
    cin>>u;
    if(u=="tri")
    {
        cout<<"everything is fine";
        
    }
    else
    {
        cout<<"Not fine";
        
    }
    
}