Cod sursa(job #1168383)
Utilizator | Cristina Borza cristina_borza | Data | 8 aprilie 2014 10:48:51 |
---|---|---|---|
Problema | Numarare triunghiuri | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.51 kb |
#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("nrtri.in");
ofstream fout("nrtri.out");
int a[801],i,j,sum,poz,n,v,d;
bool comp(int a,int b)
{
return a<b;
}
int main()
{
fin>>n;
for(i=1;i<=n;i++)
fin>>a[i];
sort(a+1,a+n+1,comp);
for(i=1;i<=n-2;i++)
{
for(j=i+1;j<=n-1;j++)
{
v=a[i]+a[j];
poz=upper_bound(a+1,a+n+1,v)-a-1;
sum=sum+poz-j;
}
}
fout<<sum;
return 0;
}