Submission #1097242

#	Time	Username	Problem	Language	Result	Execution time	Memory
1097242		vjudge1	Rack (eJOI19_rack)	C++17	100 / 100	9 ms	8028 KiB

rack

#include <bits/stdc++.h>
using namespace std;
#define ll long long int
const ll MOD = 1000000007;
int main(){
  ios_base::sync_with_stdio(false);
  cin.tie(0);
    ll n,k;
    cin >> k>>n;
    vector<ll>a(k,0LL);
    n--;
    ll i =0 ;
    while(n>0){
      a[i]=n%2LL;
      n/=2LL;
      i++;
    }reverse(a.begin(),a.end());
    ll x = 1;
    ll act = 1;
    for(ll i=0;i<a.size();i++){
      if(a[i]!=0)x+=act*a[i];
      x%=MOD;
      act*=2LL;
      act%=MOD;
    }cout << x << endl;
  
  return 0;
}

Compilation message (stderr)

rack.cpp: In function 'int main()':
rack.cpp:20:17: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |     for(ll i=0;i<a.size();i++){
      |                ~^~~~~~~~~

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