Cod sursa(job #1560309)
Utilizator | Mustea Iulia-Otilia iuliaotilia26 | Data | 2 ianuarie 2016 14:48:01 |
---|---|---|---|
Problema | Numarare triunghiuri | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.55 kb |
#include<fstream>
#include<algorithm>
using namespace std;
int v[800],n;
ifstream f("nrtri.in");
ofstream g("nrtri.out");
int main()
{
int i,j,st,dr,m;
int nr=0;
f>>n;
for(i=0;i<n;i++)f>>v[i];
sort(v,v+n);
for(i=0;i<n-1;i++)
for(j=i+1;j<n;j++)
{
st=j;
dr=n;
while(st+1<dr)
{
m=(st+dr)/2;
if(v[m]<=v[i]+v[j])st=m;
else dr=m;
}
nr=nr+st-j;
}
g<<nr;
f.close();
g.close();
return 0;
}