Submission

Score: 0

User: bbcctxp

Problemset: ตรวจบัตรเครดิต

Language: c

Time: 0.000 second

Submitted On: 2025-10-09 21:46:19

//c1_bkk67_5
#include <stdio.h>
#include <string.h>
int num[20];

int main(){
    char id[20],id_rev[20];
    scanf("%s",id);
    int check=id[15]-'0';

    strrev(id);

    for(int i=0;i<16;i++)
        if(i!=0)
            num[i]=id[i]-'0';

    for(int i=0;i<16;i++){
        if(i%2)
            num[i]*=2;
    }


    int sum=0;
    for(int i=0;i<16;i++){
        if(num[i]>=10)
            sum=sum+(num[i]/10)+(num[i]%10);
        else
            sum+=num[i];
    }

    //(10 - (R mod 10)) mod 10
    int ans=(10-(sum%10))%10;

    if(ans==check) printf("yes");
    else printf("no");


    return 0;
}
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