Submission #999711

#	Time	Username	Problem	Language	Result	Execution time	Memory
999711		vjudge1	Rack (eJOI19_rack)	C++17	100 / 100	45 ms	53760 KiB

rack

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define mod 1000000007
ll binpow(ll a, ll b){
    ll res = 1;
    if (b == -1){
        return 0;
    }
    while (b != 0){
        if (b % 2 == 0){
            b /= 2;
            a *= a;
            a %= mod;
        }
        else{
            b -= 1;
            res *= a;
            res %= mod;
        }
    }
    return res;
}
vector<vector<ll>> ve;
ll ans = 1;
ll f(ll n, ll k, ll va){
    ll val = 0;
    if (n == 0){
        return 0;
    }
    if (n <= 63){
        ll op = pow(2, n - 1);
        if (k >= op){
            val += binpow(2, va);
            ve.push_back({n - 1, k - op, va + 1});
            ans += val;
            return 0;
        }
    }
    ve.push_back({n - 1, k, va + 1});
    return 0;
}
int main(){
    ll n, k;
    cin>>n>>k;
    k--;
    ve.push_back({n, k, 0});
    for (int i = 0; i < ve.size(); i++){
        f(ve[i][0], ve[i][1], ve[i][2]);
        ans %= mod;
    }
    cout<<ans;
}

Compilation message (stderr)

rack.cpp: In function 'int main()':
rack.cpp:48:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |     for (int i = 0; i < ve.size(); i++){
      |                     ~~^~~~~~~~~~~

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