Cod sursa(job #640382)
Utilizator | Andrei Dan andreidan | Data | 25 noiembrie 2011 16:09:29 |
---|---|---|---|
Problema | Medie | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.41 kb |
#include <iostream.h>
#include<cstdio>
int a[9005],n;
int freq[7005];
int main(){
freopen("medie.in","r",stdin);
freopen("medie.out","w",stdout);
int i,j,k=0,b;
cin>>n;;
for(i=0;i<n;++i)
cin>>a[i];
for(i=0;i<n;++i){
++freq[a[i]];
}
for(i=1;i<n;++i)
for(j=0;j<i;++j)
if((a[i]+a[j])%2==0){
b=(a[i]+a[j])/2;
k=k+freq[b];
if(a[i]==a[j]) k=k-2;
}
cout<<k;;
}