Cod sursa(job #2716706)
Utilizator | Petre Adela Adela_Petre | Data | 5 martie 2021 15:58:15 |
---|---|---|---|
Problema | Numarare triunghiuri | Scor | 0 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva de probleme | Marime | 0.73 kb |
#include <iostream>
#include <algorithm>
#include <fstream>
using namespace std;
ifstream fin("nrtri.in");
ofstream fou("nrtri.out");
const int MAX = 800;
int N, i, v[1 + MAX], nr;
int main()
{
cin >> N;
for(int i = 1; i <= N; i++)
cin >> v[i];
sort(v + 1, v + N + 1);
for(int i = 1; i < N; i++)
{
for(int j = i + 1; j < N; j++)
{
int st = j + 1, dr = N, s = v[i] + v[j], mid;
while(st <= dr)
{
mid = (st + dr)/2;
if(s >= v[mid])
st = mid + 1;
else
dr = mid - 1;
}
nr += dr - j;
}
}
cout << nr;
}