Submission #778394

#	Time	Username	Problem	Language	Result	Execution time	Memory
778394		andrei_iorgulescu	Rack (eJOI19_rack)	C++14	100 / 100	8 ms	7848 KiB

rack

#include <bits/stdc++.h>

using namespace std;

#define int long long

int modulo = 1e9 + 7;
int p2[1000005];

int f(int n,int k)
{
    if (n == 0)
        return 1;
    if (k % 2 == 1)
        return f(n - 1,k / 2 + 1);
    else
        return (f(n - 1,k / 2) + p2[n - 1]) % modulo;
}

signed main()
{
    int n,k;
    cin >> n >> k;
    p2[0] = 1;
    for (int i = 1; i <= n; i++)
        p2[i] = 2 * p2[i - 1] % modulo;
    cout << f(n,k);
    return 0;
}

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