Pagini recente » Cod sursa (job #1002619) | Cod sursa (job #2136470) | Cod sursa (job #1739108) | Cod sursa (job #3163041) | Cod sursa (job #496165)
Cod sursa(job #496165)
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
struct point
{
int x;
short a,b;
point *y;
};
point *a[1000000],*t;
int b[1000000][4],c,i,l,m,j,o[1025],max,n;
int h(int k)
{
float c;
c=(sqrt(5)+1)/2;
return (int)(m*((k*c)-(int)(k*c)));
}
void insert(int k)
{
point *p;
int q;
q=h(k);
if(q>max)max=q;
p=new point;
p->x=k;
p->a=i;
p->b=j;
p->y=a[q];
a[q]=p;
}
void search(point *p)
{
int q;
bool ok;
q=h(l-p->x);
point *u;
u=a[q];
while(u)
{
if(u->x==l-p->x)
if((u->a!=p->a)&&(u->a!=p->b)&&(u->b!=p->a)&&(u->b!=p->b))
{
int v[4],i,j;
v[0]=p->a;
v[1]=p->b;
v[2]=u->a;
v[3]=u->b;
for(i=0;i<3;i++)
for(j=i+1;j<4;j++)
if(v[i]>v[j])
{
q=v[i];
v[i]=v[j];
v[j]=q;
}
ok=true;
for(i=0;i<n;i++) if(b[i][0]==v[0]&&b[i][1]==v[1]&&b[i][2]==v[2]&&b[i][3]==v[3])ok=false;
if(ok)
{
for(i=0;i<4;i++)b[n][i]=v[i];
n++;
}
}
u=u->y;
}
}
int main()
{
freopen("oite.in","r",stdin);
freopen("oite.out","w",stdout);
scanf("%d%d",&c,&l);
for(i=0;i<c;i++)scanf("%d",&o[i]);
m=c/3;
for(i=0;i<c-1;i++)
for(j=i+1;j<c;j++) insert(o[i]+o[j]);
for(i=0;i<=max;i++)
{
t=a[i];
while(t)
{
search(t);
t=t->y;
}
}
printf("%d\n",n);
}