Submission

Score: 100

User: blaboo123

Problemset: ตรวจบัตรเครดิต

Language: cpp

Time: 0.003 second

Submitted On: 2025-10-11 12:55:33

#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

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

    int sum = 0;

    for (int i = 0; i < 15; i++) {
        int digit = number_str[i] - '0';

        if (i % 2 == 0) {
            digit *= 2;
            if (digit > 9) {
                digit -= 9;
            }
        }

        sum += digit;
    }

    int check_digit = number_str[15] - '0';

    int total_sum = sum + check_digit;

    if (total_sum % 10 == 0) {
        cout << "yes" << endl;
    } else {
        cout << "no" << endl;
    }

    return 0;
}