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#include <iostream>
#include <fstream>
using namespace std;
ifstream fin ("triplete.in");
ofstream fout ("triplete.out");
int n,m,a,b;
long long s=0;
bool f[4097][4097];
int v[4097];
long long calccomb(int n, int k){
long long p=1;
for(long long d=n-k+1;d<=n;d++){
p=p*d;
}
p=p/2;
return p;
}
int main()
{
fin>>n>>m;
for(int i=1;i<=m;i++){
fin>>a>>b;
f[a][b]=1;
v[b]++;
}
for(int i=1;i<=n;i++){
if(v[i]>=2){
s=s+calccomb(v[i],2);
}
}
fout<<s;
return 0;
}