이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define fi first
#define se second
#define mp make_pair
#define pb push_back
ll n,k,ans=0;
pair<ll,ll> a[50];
vector < ll > data_left[43],data_right[43],data;
void bt_left(int start,ll val,int high){
	if(start==(n+3)/2){
			int pos=lower_bound(data.begin(),data.end(),high)-data.begin();
			data_left[pos].pb(val);
			return ;
		}
	bt_left(start+1,val,high);
	if(a[start].fi>=high){
		bt_left(start+1,val+a[start].se,a[start].fi);
	}	
			
}
void bt_right(int i,int high,int fr,ll val){
	if(i==n+1){
		int pos=lower_bound(data.begin(),data.end(),fr)-data.begin();
		data_right[pos].pb(val);
		return;
	}
	bt_right(i+1,high,fr,val);
	if(a[i].fi>=high){
		if(fr==0) 
			fr=a[i].fi;
		bt_right(i+1,a[i].fi,fr,val+a[i].se);
	}
}
int main()
{
	cin>>n>>k;
	data.pb(0);
	for(int i=1;i<=n;i++)
		{
			cin>>a[i].fi>>a[i].se;
			data.pb(a[i].fi);
		}
	sort(data.begin(),data.end());	
	//for(int i=0;i<data.size();i++)
	//	cout<<data[i]<<' ';
	//cout<<endl<<endl;		
	bt_left(1,0,0);
	bt_right((n+3)/2,0,0,0);
	n=data.size();
	for(int i=0;i<n;i++) {
			sort(data_right[i].begin(),data_right[i].end());
			//for(int j=0;j<data_right[i].size();j++)
			//	cout<<data_right[i][j]<<' ';
			//cout<<endl;	
		}
	for(int i=0;i<n;i++){
		for(int j=0;j<data_left[i].size();j++){
			ll x=data_left[i][j];
			ans+=data_right[0].end()-lower_bound(data_right[0].begin(),data_right[0].end(),k-x);
			for(int ij=i;ij<n;ij++){
				if(ij==0) continue;
				ans+=data_right[ij].end()-lower_bound(data_right[ij].begin(),data_right[ij].end(),k-x);
			}
		}
	}
	cout<<ans;
}
컴파일 시 표준 에러 (stderr) 메시지
san.cpp: In function 'int main()':
san.cpp:59:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0;j<data_left[i].size();j++){
                ^| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... |