Cod sursa(job #72193)

Utilizator blasterzMircea Dima blasterz Data 12 iulie 2007 23:52:31
Problema Oite Scor 80
Compilator cpp Status done
Runda Arhiva de probleme Marime 1 kb
using namespace std;
#include <vector>
#include <cstdio>
#include <cstdlib>
#include <string>
#define r 17
#define maxn 666713
#define ui unsigned int
struct nod { ui i, j,sum;nod *next;};

nod *H[maxn];
ui n, S;
ui x[1025];
ui nr;
void insert(ui i, ui j)
{
	nod *t=new nod;
	t->i=i; t->j=j;
	t->sum=x[i]+x[j];
	ui h=((t->sum))%maxn;
	t->next=H[h];
	H[h]=t;
}

int find(ui i, ui j)
{
	ui  sum=S-(x[i]+x[j]);
	nod *t;
	ui h=((sum))%maxn;
	for(t=H[h];t;t=t->next)
		if(t->sum==sum)
		
			if(t->i==i || t->i==j || t->j==i || t->j==j);
			else //{ printf("%d %d %d %d\n",i, j, t->i, t->j);++nr;}
			++nr;
		
	return nr;
}

int main()
{
	freopen("oite.in","r",stdin);
	scanf("%d %d\n", &n, &S);
	int i, j;
	//	init();
	
	for(i=1;i<=n;++i) scanf("%d ", x+i);
	
	for(i=1;i<n;++i)
		for(j=i+1;j<=n;++j)
			insert(i,j);
		
	

	
	for(i=1;i<n;++i)
		for(j=i+1;j<=n;++j)
			find(i, j);
		
	freopen("oite.out","w",stdout);
	printf("%d\n", nr/6);
	return 0;
}