Cod sursa(job #2640616)
Utilizator | Data | 7 august 2020 01:35:56 | |
---|---|---|---|
Problema | Numarare triunghiuri | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva de probleme | Marime | 0.6 kb |
#include <algorithm>
#include <fstream>
using namespace std;
int i,j,n,v[805],sol,k;
int main()
{
ifstream f("nrtri.in");
ofstream g("nrtri.out");
f>>n;
for (i=1;i<=n;i++)
f>>v[i];
sort(v+1,v+n+1);
for (i=1;i<=n-2;i++) {
for (j=i+1;j<n;j++) {
k=j+1;
while (k<n && v[k]<=v[i]+v[j]) k++;
if (k==n)
{
if (v[k]==v[i]+v[j]) sol+=k-j;
else if (v[k]>v[i]+v[j]) sol+=k-j-1;
else sol+=n-j;
}
else if (v[k]>v[i]+v[j]) sol+=k-j-1;
}
}
g<<sol;
}