제출 #1121535

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1121535		coolboy19521	Ice Hockey World Championship (CEOI15_bobek)	C++17	100 / 100	399 ms	8776 KiB

bobek

#include"bits/stdc++.h"
using namespace std;

using ll = long long;

const int mxN = 40;

ll a[mxN];

main() {
    int N;
    ll M;
    cin >> N >> M;

    for (int i = 0; i < N; i ++) {
        cin >> a[i];
    }

    int firstHalf = N / 2;
    vector<ll> poss;
    for (int i = 0; i < (1 << firstHalf); i ++) {
        ll sm = 0;
        for (int j = 0; j < firstHalf; j ++) {
            if ((i >> j) & 1) {
                sm += a[j];
            }
        }
        poss.push_back(sm);
    }

    sort(begin(poss),end(poss));

    int secondHalf = N - firstHalf;
    ll ans = 0;
    for (int i = 0; i < (1 << secondHalf); i ++) {
        ll sm = 0;
        for (int j = 0; j < secondHalf; j ++) {
            if ((i >> j) & 1) {
                sm += a[firstHalf + j];
            }
        }
        ans += upper_bound(begin(poss),end(poss),M - sm) - begin(poss);
    }

    cout << ans << endl;
}

컴파일 시 표준 에러 (stderr) 메시지

bobek.cpp:10:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   10 | main() {
      | ^~~~

• 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