Сумма

#include <bits/stdc++.h>

using namespace std;

int main(){
    ios::sync_with_stdio(0);

    long long n, revN = 0, temp;

    cin >> n;

    temp = n;

    while (temp > 0) {
        int x = temp % 10;
        revN = revN * 10 + x;
        temp /= 10;
    }

    cout << n + revN << endl;
}