Submission

Score: 100

User: denze

Problemset: ตรวจบัตรเครดิต

Language: cpp

Time: 0.002 second

Submitted On: 2025-10-12 22:07:26

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

char s[20];
int a[20];

int main()
{
    scanf("%s", s);
    int n = strlen(s);
    int lastdigit = s[n - 1] - '0';
    n--;
    for (int i = 0; i < n; i++)
    {
        a[i] = s[i] - '0';
    }
    for (int i = 0; i < n / 2; i++)
    {
        swap(a[i], a[n - 1 - i]);
    }
    for (int i = 0; i < n; i += 2)
    {
        a[i] *= 2;
    }
    int r = 0;
    for (int i = 0; i < n; i++)
    {
        if (a[i] > 9)
        {
            r += a[i] / 10;
            r += a[i] % 10;
        }
        else
        {
            r += a[i];
        }
    }
    if (lastdigit == (10 - (r % 10)) % 10)
    {
        printf("yes");
    }
    else
    {
        printf("no");
    }
}

/*
3
*/