Submission #155004

#	Time	Username	Problem	Language	Result	Execution time	Memory
155004		TadijaSebez	Ice Hockey World Championship (CEOI15_bobek)	C++11	100 / 100	442 ms	16892 KiB

bobek

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
const int N=43;
ll a[N],K;
int n;
vector<ll> Build(int l, int r)
{
	int sz=r-l+1;
	vector<ll> ans;
	ans.reserve(1<<sz);
	for(int mask=0;mask<1<<sz;mask++)
	{
		ll sum=0;
		for(int i=0;i<sz;i++) if(mask>>i&1) sum+=a[l+i];
		ans.pb(sum);
	}
	sort(ans.begin(),ans.end());
	return ans;
}
int main()
{
	scanf("%i %lld",&n,&K);
	for(int i=1;i<=n;i++) scanf("%lld",&a[i]);
	int m=n/2;
	vector<ll> L,R;
	L=Build(1,m);
	R=Build(m+1,n);
	ll ans=0;
	for(int i=0;i<L.size();i++)
	{
		int j=upper_bound(R.begin(),R.end(),K-L[i])-R.begin();
		ans+=j;
	}
	printf("%lld\n",ans);
	return 0;
}

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:31:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<L.size();i++)
              ~^~~~~~~~~
bobek.cpp:24:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%i %lld",&n,&K);
  ~~~~~^~~~~~~~~~~~~~~~~
bobek.cpp:25:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=1;i<=n;i++) scanf("%lld",&a[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