Submission #208569

#	Time	Username	Problem	Language	Result	Execution time	Memory
208569		fr_klr	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	244 ms	20944 KiB

bobek

//You can't fill the hole inside you with money, drugs and cars
#include<bits/stdc++.h>
using namespace std;

long long n, m;
vector<long long> v, a, b;

void create(int st, int en, vector<long long> &w){
    int sz = en - st;
    w.push_back(0);
    for(int mask = 1; mask < (1 << sz); mask++)
        w.push_back(w[mask - (mask & -mask)] + v[st + __builtin_ctz(mask)]);

}

long long inp(){
    long long A;
    cin >> A;
    return A;
}

void input(){
    cin >> n >> m;
    for(int i = 0; i < n; i++)
        v.push_back(inp());
}

long long matches(int p1 = 0, int p2 = b.size() - 1, long long ans = 0){
    sort(a.begin(), a.end());
    sort(b.begin(), b.end());

    for(auto A : a){
        while(p2 >= 0 and A + b[p2] > m)
            p2--;
        ans += (p2 + 1);
        if(p2 < 0)
            break;
    }
    return ans;
}

long long solve(){
    int mid = n / 2;
    create(0, mid, a);
    create(mid, n, b);

    return matches();
}

int main(){
    input();
    cout << solve();
}

• 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