Submission #43508

#	Time	Username	Problem	Language	Result	Execution time	Memory
43508		XmtosX	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	440 ms	25376 KiB

bobek

#include <bits//stdc++.h>
using namespace std;
const int mod=1e9+7;
int n;
long long m,a[50];
vector <long long> v1,v2;
void bt (int pos,int x,long long sum)
{
    if (pos==x)
    {
        if (x==n)
            v2.push_back(sum);
        else
            v1.push_back(sum);
        return;
    }
    bt(pos+1,x,sum);
    bt(pos+1,x,sum+a[pos]);
}
int main()
{
    cin >>n>>m;
    for (int i=0;i<n;i++)
        cin >>a[i];
    v2.push_back(m+1);
    bt(0,n/2,0);
    bt(n/2,n,0);
    sort(v2.begin(),v2.end());
    long long ans=0;
    for (int i=0;i<v1.size();i++)
    {
        long long x=(m-v1[i]);
        ans+= ((upper_bound(v2.begin(),v2.end(),x)-v2.begin()));
    }
    cout <<ans;
    return 0;
}

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:30:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i=0;i<v1.size();i++)
                   ^

• 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