Cod sursa(job #566119)
Utilizator | Moraru Valentina valentina506 | Data | 28 martie 2011 17:42:05 |
---|---|---|---|
Problema | Medie | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.43 kb |
#include<fstream>
using namespace std;
struct ap
{
int p,nr;
};
ap b[7001];
unsigned int n,i,j,a[9001], p[7001],sum;
int main()
{
ifstream f("medie.in");
ofstream g("medie.out");
f>>n;
for(i=1;i<=n;i++)
{
f>>a[i];
b[a[i]].nr++;
for(j=i-1;j>0;j--)
if((a[i]+a[j])%2==0)
b[(a[i]+a[j])/2].p++;
}
for(i=1;i<=n;i++)
{
//g<<p[i]<<" ";
sum+=b[a[i]].p-b[a[i]].nr+1;
}
g<<sum;
return 0;
}