Kyselyt

#include <iostream>

using namespace std;
typedef long long ll;

ll power(ll a, ll b) {
    if(b == 0) {
        return 1;
    }
    if(b%2 == 0) {
        ll c = power(a, b/2);
        c = c*c;
        return c;
    }
    ll c = power(a,b - 1);
    return a * c;
}

int main() {
    int q;
    cin >> q;
    for(int a = 1; a <= q; a++) {
        ll k;
        cin >> k;
        ll digits = 1;
        ll amount = 9;
        ll total = 9;
        while(total < k) {
            digits++;
            amount *= 10;
            total += digits*amount;
        }
        total -= digits*amount;
        ll rem = (k-total)%digits;
        ll whole = (k-rem - total)/digits;
        whole = whole + power(10, digits - 1) - 1;
        int digitTable[100];
        int index = 0;
        while(whole > 0) {
            int digit = whole%10;
            digitTable[index] = digit;
            index++;
            whole = whole/10;
        }
        cout << digitTable[rem] << "\n";
    }
}

Test 1

Group: 1

Verdict: WRONG ANSWER

Test 2

Group: 2

Verdict: WRONG ANSWER

Test 3

Group: 3

Verdict: WRONG ANSWER