Submission

Score: 100

User: Bunkoblong

Problemset: ตรวจบัตรเครดิต

Language: cpp

Time: 0.003 second

Submitted On: 2025-10-02 17:03:56

#include<iostream>
#include<string>

using namespace std;
int main(){
    string c;
    while(cin>>c){
    int n=0;
    bool doubleDigit=false;
    
    for(int i=c.size()-1;i>=0;i--){
        int digit=c[i]-'0';
        
        if(doubleDigit){
            digit=digit*2;
            if(digit>9){
                digit=digit-9;
            }
        }
        n+=digit;
        doubleDigit= !doubleDigit;
    }
    if (n%10==0){
        cout<<"yes";
    } else{
        cout<<"no";
    }
    }
 
}