Cod sursa(job #2064430)
Utilizator | Ayy LMAO TheNextGeneration | Data | 12 noiembrie 2017 12:54:05 |
---|---|---|---|
Problema | Numarare triunghiuri | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.69 kb |
#include <bits/stdc++.h>
using namespace std;
ifstream cin("nrtri.in");
ofstream cout("nrtri.out");
int v[805];
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n,nr=0;
cin >> n;
for (int i = 1; i<=n; i++)
cin >> v[i];
sort(v+1,v+n+1);
for (int i = 1; i<=n-2; i++)
for (int j = i+1; j<=n; j++)
{
int st = j+1, dr = n;
while (st<=dr)
{
int mj = (st+dr)/2;
if (v[mj]>v[i]+v[j])
dr = mj-1;
else
st = mj+1;
}
nr+=st-j-1;
}
cout << nr;
}