Cod sursa(job #902711)

Utilizator misinoonisim necula misino Data 1 martie 2013 16:19:14
Problema Triplete Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.61 kb
#include<fstream>
using namespace std;
ifstream f("triplete.in");
ofstream g("triplete.out");
int n,m,i,j,x,y,sol,nrb[(1<<16)+5],a[4100][300];
struct nod{int x,y;};
nod v[65600];
int main()
{
    f>>n>>m;
    for(i=1;i<=65600;++i)
    nrb[i]=nrb[i>>1]+(i&1);
    for(i=1;i<=m;++i)
    {
        f>>v[i].x>>v[i].y;
        x=v[i].x;
        y=v[i].y;
        a[x][y/16]+=(1<<(y%16));
        a[y][x/16]+=(1<<(x%16));
    }
    for(i=1;i<=m;++i)
    {
        x=v[i].x;
        y=v[i].y;
        for(j=0;j<=n/16;++j)
        sol+=nrb[a[x][j]&a[y][j]];
    }
    g<<sol/3<<'\n';
    return 0;
}