Kyselyt

#include <bits/stdc++.h>
using namespace std;
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define IO ios_base::sync_with_stdio(0); cin.tie(0)
typedef long long ll;

ll q;
ll r[20];

ll solve(ll k) {
	ll d = 0;
	FOR(i,1,18) if (k < r[i]) { d = i; break; } 
	ll n = r[d-1] + 1;
	ll b = (k - n) / d;
	ll p = n + b * d;
	ll w = d - 1 - (k - p);
	ll r = (ll)(b / pow(10,w)) % 10;
	if (w == d-1) r++;
	return r;
}

int main() {
	IO; cin>>q;
	r[1] = 9;
	FOR(d,2,18) r[d] = r[d-1]+d*9*pow(10,d-1);
	FOR(inp,0,q) {
		ll k; cin>>k;
		cout << solve(k) << "\n";
	}
}

Test 1

Group: 1

Verdict: WRONG ANSWER

Test 2

Group: 2

Verdict: ACCEPTED

Test 3

Group: 3

Verdict: WRONG ANSWER