一道图论小题目

#include <fstream>
#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <cstdlib>

using namespace std;

#define PI acos(-1.0)
#define EPS 1e-10
#define lll __int64
#define ll long long
#define INF 0x7fffffff

const int N=10005;
int du
;

int main(){
//freopen("D:\\input.in","r",stdin);
//freopen("D:\\output.out","w",stdout);
int n,m,t1,t2;
scanf("%d %d",&n,&m);
for(int i=0;i<m;i++){
scanf("%d %d",&t1,&t2);
du[t1]++,du[t2]++;
}
ll ans=0;
for(int i=1;i<=n;i++)   ans+=(ll)du[i]*du[i];
printf("%lld\n",ans);
return 0;
}