Submission #466175

#	Time	Username	Problem	Language	Result	Execution time	Memory
466175		MKutayBozkurt	Rack (eJOI19_rack)	C++14	40 / 100	1 ms	204 KiB

rack

#include <iostream>
#include <vector>
#include <algorithm>
#include <bits/stdc++.h>
using namespace std;

#define int long long
const int mod = 1e9 + 7;

int32_t main() {
  ios::sync_with_stdio(0); cin.tie(0);
  function<int(int, int)> power = [&](int a, int b) {
    int ans = 1;
    while (b) {
      if (b & 1) ans = ans * a % mod;
      a = a * a % mod;
      b /= 2;
      ans %= mod;
    }
    return ans % mod;
  };
  function<int(int, int)> f = [&](int n, int k) {
    if (n == 0ll) return 1ll;
    if (k & 1) {
      return f(n - 1, (k + 1) / 2);
    } else {
      return f(n - 1, k / 2) + power(2, n - 1) % mod;
    }
  };
  int n, k; cin >> n >> k;
  cout << f(n, k) << '\n';
}

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