Submission #377307

#	Time	Username	Problem	Language	Result	Execution time	Memory
377307		gustason	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	538 ms	25100 KiB

bobek

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    ll m;
    cin >> n >> m;
    vector<ll> l, r;
    for(int i = 0; i < n; i++) {
        ll x;
        cin >> x;
        if (i > n/2) {
            r.push_back(x);
        } else {
            l.push_back(x);
        }
    }

    vector<ll> ls, rs;
    const int ln = l.size(), rn = r.size();
    for(int mask = 0; mask < (1 << ln); mask++) {
        ll sum = 0;
        for(int i = 0; i < ln; i++) {
            if (mask & (1 << i)) {
                sum += l[i];
            }
        }
        ls.push_back(sum);
    }
    for(int mask = 0; mask < (1 << rn); mask++) {
        ll sum = 0;
        for(int i = 0; i < rn; i++) {
            if (mask & (1 << i)) {
                sum += r[i];
            }
        }
        rs.push_back(sum);
    }

    ll ans = 0;
    sort(ls.begin(), ls.end());
    sort(rs.begin(), rs.end());
    for(ll i : ls) {
        ll idx = upper_bound(rs.begin(), rs.end(), m - i) - rs.begin();
        ans += idx;
    }
    cout << ans << "\n";
    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: 10 / 10