Submission #832124

#	Time	Username	Problem	Language	Result	Execution time	Memory
832124		KaleemRazaSyed	Rack (eJOI19_rack)	C++17	100 / 100	8 ms	7892 KiB

rack

#include<bits/stdc++.h>

using namespace std;

const int N = 1e6+5 , mod = 1e9+7;
long long pw[N];

long long f(long long k, int n)
{
  // cerr << "f(" << k << ", " << n << ")\n";
  if(n==0)
    return k;
  long long l = k/2 + k%2;
  long long r = k/2;
  if(l==r)
    return (pw[n-1]+f(r, n-1))%mod;
  return f(l, n-1);    
}

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

  pw[0] = 1;
  for(int i=1;i<=n;i++)
    pw[i] = (pw[i-1]*2)%mod;
  cout << f(k, n) << endl;
  return 0;
}

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