Submission #638791

#	Time	Username	Problem	Language	Result	Execution time	Memory
638791		HossamHero7	Ice Hockey World Championship (CEOI15_bobek)	C++14	90 / 100	1060 ms	60868 KiB

bobek

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
#define endl '\n'
#pragma GCC optimize("O2")
void solve(){
    ll n,m;
    cin>>n>>m;
    vector<ll> v(n);
    for(auto &i:v) cin>>i;
    unordered_map<ll,int> frq;
    for(int mask=0;mask<(1<<n/2);mask++){
        ll sum = 0;
        for(int i=0;i<(n>>1);i++){
            if((1<<i)&mask){
                sum += v[i];
            }
        }
        frq[sum] ++;
    }
    int prev = 0;
    vector<ll> tmp;
    for(auto &i : frq){
        tmp.push_back(i.first);
    }
    sort(tmp.begin(),tmp.end());
    for(auto i : tmp){
        frq[i] += prev;
        prev = frq[i];
    }
    int rem = n-(n>>1);
    ll ans = 0;
    for(int mask=0;mask<(1<<rem);mask++){
        ll sum = 0;
        for(int i=0;i<rem;i++){
            if((1<<i)&mask){
                sum += v[(n>>1)+i];
            }
        }
        if(sum > m) continue;
        int upper = upper_bound(tmp.begin(),tmp.end(),m-sum) - tmp.begin();
        upper --;
        ans += frq[tmp[upper]];
    }
    cout<<ans<<endl;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);      cout.tie(0);
    solve();
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 0 / 10