Kyselyt

#include <iostream>
#include <sstream>
#include <cstdint>

#define dt uint64_t

using namespace std;

dt getDigits(dt value) { // Max 64 bit: ~9000000000000000000
    if (value < 10) {
    	return 1;
    } else if (value < 100) {
    	return 2;
    } else if (value < 1000) {
    	return 3;
    } else if (value < 10000) {
    	return 4;
    } else if (value < 100000) {
    	return 5;
    } else if (value < 1000000) {
    	return 6;
    } else if (value < 10000000) {
    	return 7;
    } else if (value < 100000000) {
    	return 8;
    } else if (value < 1000000000) {
    	return 9;
    } else if (value < 10000000000) {
    	return 10;
    } else if (value < 100000000000) {
    	return 11;
    } else if (value < 1000000000000) {
    	return 12;
    } else if (value < 10000000000000) {
    	return 13;
    } else if (value < 100000000000000) {
    	return 14;
    } else if (value < 1000000000000000) {
    	return 15;
    } else if (value < 10000000000000000) {
    	return 16;
    } else if (value < 100000000000000000) {
    	return 17;
    } else if (value < 1000000000000000000) {
    	return 18;
    }
    return 19;
}

int main() {
	dt amount;
	cin >> amount;
	dt *a = new dt[amount];
	dt cur;
	dt index;
	dt size;
	dt digits;
	dt minus;
	for (dt i = 0; i < amount; i++) {
		cin >> a[i];
	}
	for (dt i = 0; i < amount; i++) {
		cur = a[i];
		index = 1;
		size = 0;
		digits = 0;
		minus = 1;
		ostringstream ss;

		for (; size <= cur; index++) {
			digits = getDigits(index);
			if (size + digits >= cur) {
				ss << index;
			} else {
				minus += digits;
			}
			size += digits;
		}
		cout << ss.str().at(cur - minus) << '\n';
	}
	//while (1);
	return 0;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED

Test 3

Group: 3

Verdict: TIME LIMIT EXCEEDED