Cod sursa(job #2935801)
Utilizator | LiliPop Lily.pop | Data | 7 noiembrie 2022 16:07:41 |
---|---|---|---|
Problema | Numarare triunghiuri | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva de probleme | Marime | 0.77 kb |
#include <fstream>
#include <algorithm>
using namespace std;
ifstream cin("nrtri.in");
ofstream cout("nrtri.out");
int n,v[801],nr,i,j,st,dr,sol,s,mij;
int main()
{
cin>>n;
for(i=1; i<=n; i++)
{
cin>>v[i];
}
sort(v+1,v+n+1);
for(i=1; i<n; i++)
{
for(j=i+1; j<=n; j++)
{
s=v[i]+v[j];
st=j;
dr=n;
while(st<=dr)
{
mij=(st+dr)/2;
if(v[mij]>s)
{
dr=mij-1;
}
else
{
st=mij+1;
sol=mij;
}
}
nr=nr+sol-j;
}
}
cout <<nr;
return 0;
}