Submission

----------

Score: 0

User: mydKN

Problemset: เลขหลักของผลคูณ

Language: cpp

Time: 0.002 second

Submitted On: 2024-10-16 21:14:40

#include <stdio.h>

#define ll long long

ll power(ll n, ll x){
    ll i;
    ll res = 1;
    for(i=0;i<x;++i){
        res *= n;
    }
    return res;
}

ll solve(ll x){
    if(x > 0) return x;
    return 0;
}

int main(){
    ll a, b, x;
    printf("A = ");
    scanf("%lld", &a);
    printf("B = ");
    scanf("%lld", &b);
    printf("x = ");
    scanf("%lld", &x);
    ll sum = a * b;
    ll i;
    ll cnt = 0;
    for(i=1;sum>i;i*=10) cnt++;
    //printf("%lld", i);
    if(x < 0 || x > cnt) printf("_");
    else if(x == cnt) printf("%lld", sum%10);
    else{
        printf("%lld", (solve((sum%power(10, cnt-x+1))-(sum%(power(10, cnt-x))))/power(10, cnt-x)));
    }
}