Submission #453232

#	Time	Username	Problem	Language	Result	Execution time	Memory
453232		lukadupli	Rack (eJOI19_rack)	C++14	100 / 100	5 ms	204 KiB

rack

#include <bits/stdc++.h>

using namespace std;

const int MAX = 1e6 + 5, MOD = 1e9 + 7;

int n, sol;
long long k;

bool binary[MAX];

int main()
{
    cin >> n >> k;
    k--;

    for(int i = 0; i < min(n, 64); i++){
        if(k & (1LL << i)) binary[n - i - 1] = 1;
    }

    int pow2 = 1;
    for(int i = 0; i < n; i++){
        if(binary[i]) sol = (sol + pow2) % MOD;
        pow2 = (pow2 * 2) % MOD;
    }

    cout << (sol + 1) % MOD;

    return 0;
}

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