没用函数 20分 样例都过了QAQ

#include<bits/stdc++.h>
using namespace std;
int n,k,ans,cut,m,j;
int main()
{
    cin >> n >> k;
    cut = n;
    while(cut > 0){
    	ans++;
    	cut /= 10;
    }
    m = ans - k;
    j = pow(10,m);
    cout << n / j % 10;
}