Submission #466154

#	Time	Username	Problem	Language	Result	Execution time	Memory
466154		okaragul	Rack (eJOI19_rack)	C++17	100 / 100	2 ms	204 KiB

rack

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

#define ll long long
#define endl "\n"
#define all(aa) aa.begin(), aa.end()
#define mod 1'000'000'007

ll fp(int base, int power){
	if(!power) return 1;
	ll res = fp(base, power/2);
	if(power&1) return res * res % mod * base % mod;
	else return res * res % mod;
}

int main(){
	ll n, k;
	cin>>n>>k;

	ll ans=1;
	while(n--){
		if(k%2==0) ans=(ans+fp(2, n))%mod;
		k=(k+1)/2;
	}
	cout<<ans<<endl;
}

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