Submission #1364617

#	Time	Username	Problem	Language	Result	Execution time	Memory
1364617		kmath628	Rack (eJOI19_rack)	C++20	100 / 100	6 ms	7952 KiB

rack

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll mod = 1000000007;
ll p2[1000009];
int main(){
    int n,i,c=0;
    ll k,ans=0;
    scanf("%d %lld",&n,&k);
    p2[0]=1;
    for(i=1;i<=n;i++) p2[i]=p2[i-1]*2%mod;
    k--;
    while(k>0){
        if(k%2) ans+=p2[n-1-c];
        c++;
        k/=2;
    }
    ans=(ans+1)%mod;
    printf("%lld\n",ans);
    return 0;
}

Compilation message (stderr)

rack.cpp: In function 'int main()':
rack.cpp:9:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 |     scanf("%d %lld",&n,&k);
      |     ~~~~~^~~~~~~~~~~~~~~~~

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