Submission #759213

#	Time	Username	Problem	Language	Result	Execution time	Memory
759213		sofija6	Ice Hockey World Championship (CEOI15_bobek)	C++14	60 / 100	1085 ms	161152 KiB

bobek

#include <bits/stdc++.h>
#define ll long long
#define MAXN 50
using namespace std;
ll a[MAXN],m,l,r;
set<ll> s1,s2;
map<ll,ll> cnt1,cnt2;
void Solve_1(ll cur,ll pos)
{
    if (pos>r)
    {
        if (cur>m)
            return;
        s1.insert(cur);
        cnt1[cur]++;
        return;
    }
    Solve_1(cur,pos+1);
    Solve_1(cur+a[pos],pos+1);
}
void Solve_2(ll cur,ll pos)
{
    if (pos>r)
    {
        if (cur>m)
            return;
        s2.insert(cur);
        cnt2[cur]++;
        return;
    }
    Solve_2(cur,pos+1);
    Solve_2(cur+a[pos],pos+1);
}
int main()
{
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    ll n,ans=0;
    cin >> n >> m;
    for (ll i=1;i<=n;i++)
        cin >> a[i];
    l=1;
    r=n/2;
    Solve_1(0,1);
    l=n/2+1;
    r=n;
    Solve_2(0,n/2+1);
    ll cur=0;
    for (auto i : s2)
    {
        cur+=cnt2[i];
        cnt2[i]=cur;
    }
    for (auto i : s1)
    {
        auto it=s2.lower_bound(m-i);
        if ((*it)!=m-i)
        {
            if (it==s2.begin())
                continue;
            it--;
        }
        ans+=cnt1[i]*cnt2[*it];
    }
    cout << ans;
    return 0;
}

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