Submission #899359

#	Time	Username	Problem	Language	Result	Execution time	Memory
899359		Sputnik123	Rack (eJOI19_rack)	C++14	100 / 100	1 ms	464 KiB

rack

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <string.h>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <functional>
#include <cstdio>
#define pb push_back
#define in insert
#define pll pair<ll,ll>
#define vpl vector<pll>
#define vll vector <ll>
#define vl vector<ll>
///#define mp make_pair
#define F first
#define S second
#define all(v) v.begin(),v.end()
#define endl "\n"
#define ll long long
#define ull unsigned long long
using namespace std;
using namespace __gnu_pbds;
//#pragma GCC optimize("Ofast,unroll-loops")
//#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt,fma")
const ll sz=2e6+5;
const ll inf=1e12+7;
const ll mod=1e9+7;
ll n,k,x,y,l,r;
ll modm(ll a,ll n,ll P)
{
    if(n==0)    return 1;
    if(!(n&1))
        return modm((a*a)%P,n>>1,P);
    return (a*modm(a,n-1,P))%P;
}
ll lcm(ll a,ll b)
{
    return (a/__gcd(a,b))*b;
}
void solve()
{
    cin>>n>>k;
    ll ans=0;
    k--;
    while(k)
    {
        n--;
        if(k&1)
        {
            ans+=modm(2,n,mod);
            ans%=mod;
        }
        k/=2;
    }
    cout<<ans+1<<endl;
}
///f[i]=f[i-1]+f[i+1]
///f[i+1]=f[i]-f[i-1]
///f[i]=f[i-1]-f[i-2]
int main ()
{
    //pre();
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    ll t=1;
    ///cin>>t;
    while(t--)
    {
        solve();
    }
}

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