#include<bits/stdc++.h>
#include "hall.h" 
#define L(i, j, k) for(int i = (j); i <= (k); ++i)
#define R(i, j, k) for(int i = (j); i >= (k); --i)
#define ll long long 
#define vi vector < int > 
#define sz(a) ((int) (a).size())
#define ll long long 
#define ull unsigned long long
#define me(a, x) memset(a, x, sizeof(a)) 
using namespace std;

int solve(int n,int K,int s){
	int sum = 0;
	L(i, 0, n - 1) {
		if(s >> i & 1) {
			sum += i;
		} 
	}
	sum %= K;
	L(i, 0, n - 1) {
		if(s >> i & 1) {
			if(sum == 0) {
				return s - (1 << i);
			}
			--sum;
		}
	}
	return -1;
}