UVA 10469 - To Carry or not to Carry

#include<bits/stdc++.h>
#define printCase cout << "Case "<< ++kase<<":"
#define sf scanf
#define pf printf
#define FAST ios_base::sync_with_stdio(false)
using namespace std;

int main()
{
FAST;
unsigned long long a , b;
    while(cin >> a >> b){
        string s1 , s2 , total;
        s1 =bitset<32>(a).to_string();
        s2 =bitset<32>(b).to_string();

        for (int i = 0; i < s1.length(); ++i)
        {
            if(s1[i] == '1' && s2[i] !='1' ||s1[i] != '1' && s2[i] =='1' )
                total+='1';
            else
                total+='0';
        }
        unsigned long long num ;
        num = bitset<32>(total).to_ulong();
        cout << num << '\n';
    }
return 0;
}

Another solution


int main()
{
FAST;
unsigned long long a , b;
    while(cin >> a >> b){
     
        unsigned long long num ;
        num = a^b;
        cout << num << '\n';
    }
return 0;
}