Submission #1151148

#	Time	Username	Problem	Language	Result	Execution time	Memory
1151148		yamtllq	Rack (eJOI19_rack)	C++20	40 / 100	0 ms	328 KiB

rack

#include <bits/stdc++.h>

using namespace std;

int n;
const int mod = 1e9 + 7;
long long k;
int arr[1000001];

int main(){
	cin >> n >> k;//n <= 1e6, k <= 1e18
	arr[0] = 1;
	for (int i = 1; i <= n; i++){
		arr[i] = (arr[i - 1] * 2) % mod;//n
	}
	int ans = 0;
	while (k > 1){
		int p = log2(k);
		if (arr[p] == k){
			p--;
		}
		ans = (ans + arr[n - p - 1]) % mod;
		k -= arr[p];
	}
	cout << ans + 1;
}

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 0 / 60