Kyselyt

#include <bits/stdc++.h>
using namespace std;

long long int func1(int a) {
	int b = 10;
	for (int i = 1; i < a; i++) {
		b += 9 * (int)pow(10, i) * (i + 1);
	}
	return b;
}

long long int func2(int a) {
	return (int)pow(10, a);
}

int main() {
	int q;
	cin >> q;

	long long int k[q];
	for (int i = 0; i < q; i++) {
		cin >> k[i];
	}

	for (long int i = 0; i < q; i++) {
		long int a = 1;
		if (k[i] < 10) {
			cout << k[i] << endl;
		} else {
			while (true) {
				if (k[i] < func1(a+1)) {
					long long int l = k[i] - func1(a);
					long long int num = ((l - (l%(a+1))) / (a+1)) + func2(a);
					cout << to_string(num)[l%(a+1)] << endl;
					break;
				}
				a++;
			}
		}
	}
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED

Test 3

Group: 3

Verdict: TIME LIMIT EXCEEDED