o分求助

为什么直接计算小数点后数字比较不行

#include<iostream>

using namespace std;

double getpoint(long double n){


    long double nTemp=n-int(n);
    
    return nTemp;
    
}

int main(){

    long double a,b;
    
    cin>>a>>b;
    
    getpoint(a);
    
    getpoint(b);
    
    cout<<a<<b;
    
    if(a==b) cout<<"YES";
    
    else cout<<"NO";
    
    return 0;
    
}