Submission #464465

#	Time	Username	Problem	Language	Result	Execution time	Memory
464465		kilikuma	Rack (eJOI19_rack)	C++14	100 / 100	19 ms	15532 KiB

rack

#include <bits/stdc++.h> 
using namespace std;
long long MOD = (1000*1000*1000)+7; 
long long puis(int a, int b) {
  long long res =1 ;
  for (int i=0;i<b;i++) res = res*a; 
  return res; 
}
long long val(int niveau, long pos) {
  if (niveau == 1) {
    if (pos == 1) return 1; 
    else return 2; 
  }
  if (niveau >= 61) {
    long long res = val(niveau-1, pos); 
    res = ((res*2) - 1)%MOD ; 
    return res; 
  }
  if (pos <= (puis(2, niveau-1))) {
    long long res = val(niveau-1, pos); 
    res = ((res*2)- 1)%MOD; 
    return res; 
  }
  else {
    pos -= puis(2, niveau-1); 
    long long res = val(niveau-1, pos); 
    res = (res*2)%MOD; 
    return res; 
  }
}
int main() {
  long long n, k; 
  cin >> n >> k; 
  cout << val(n, k); 
}

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