Submission #874363

#	Time	Username	Problem	Language	Result	Execution time	Memory
874363		bobbilyking	Ice Hockey World Championship (CEOI15_bobek)	C++17	100 / 100	182 ms	16872 KiB

bobek

#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")

#include<bits/stdc++.h>
#include<math.h>
using namespace std;

typedef long long int ll;
typedef long double ld;
typedef pair<ll, ll> pl;

#define K first
#define V second
#define G(x) ll x; cin >> x;
#define GD(x) ld x; cin >> x;
#define GS(s) string s; cin >> s;
#define EX(x) { cout << x << '\n'; exit(0); }
#define A(a) (a).begin(), (a).end()
#define F(i, l, r) for (ll i = (l); i < r; ++i)

#define NN
#define M 1000000007 // 998244353


int main(){
//    freopen("a.in", "r", stdin);
//    freopen("a.out", "w", stdout);

    ios_base::sync_with_stdio(false); cin.tie(0);
    cout << fixed << setprecision(20);
    G(n) G(k)
    vector<ll> v(n); for (auto &x: v) cin >> x;

    if (n == 1){
        cout << 1 + (v[0] <= k)* v[0] << '\n';
        exit(0);
    }
    ll hlf = n/2;
    
    vector<ll> th(1<<hlf);
    
    F(bm, 0, 1<<(hlf)) {
        ll s = 0;
        F(i, 0, hlf) if ((1<<i)&bm) s += v[n-hlf+i];
        th[bm] = s;
    }
    hlf = n-hlf;
    vector<ll> th2(1<<hlf);
    F(bm, 0, 1<<hlf) {
        ll s = 0;
        F(i, 0, hlf) if ((1<<i)&bm) s += v[i];
        th2[bm] = s;
    }
    sort(A(th)); sort(A(th2));
    ll rp = th2.size()-1;
    ll ans = 0;

    for (const auto &x: th) {
        while (rp >= 0 and x + th2[rp] > k) --rp;
        ans += rp+1;
    }
    cout << ans << '\n';
}

• 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