Cod sursa(job #2484307)
Utilizator | Cretoiu Patricia PatriciaCretoiu | Data | 30 octombrie 2019 22:06:01 |
---|---|---|---|
Problema | Numarare triunghiuri | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva de probleme | Marime | 0.65 kb |
#include <bits/stdc++.h>
using namespace std;
ifstream in("nrtri.in");
ofstream out("nrtri.out");
int n,i,j,st,dr,m,pos,ans;
int v[802];
int main()
{
in>>n;
for(i=1; i<=n; i++)
in>>v[i];
sort(v+1,v+1+n);
for(i=1; i<n-1; i++)
for(j=i+1; j<n; j++)
{
st=1;
dr=n;
while(st<=dr)
{
m=(st+dr)/2;
if(v[m]>v[i]+v[j])
dr=m-1;
else
{
pos=m;
st=m+1;
}
}
ans+=(pos-j);
}
out<<ans;
}