Submission

Score: 100

User: chokun

Problemset: ตรวจบัตรเครดิต

Language: cpp

Time: 0.003 second

Submitted On: 2026-10-12 20:23:33

#include <bits/stdc++.h>
using namespace std;

int main(){
    string card;
    cin >> card;

    int last_digit = card[15] - '0';

    int r = 0;
    for (int i = 0; i < 15; i++){
        int val = card[i] - '0';

        int position_frome_back = 15 - i;
        if(position_frome_back % 2 != 0){
            val *= 2;
        }

        r += (val / 10) + (val % 10);
    }
    
    int calculated_last_digit = (10 -(r % 10)) % 10;

    if(calculated_last_digit == last_digit){
        cout << "yes";
    }else{
        cout << "no";
    }
}