#include<cstring>

 #include<cmath>

 #include<iostream>

 #include<algorithm>

 #include<cstdio>

 using namespace std;

 inline int read()

 {

     int x=,f=;char ch=getchar();

     while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}

     while(ch>=''&&ch<=''){x=(x<<)+(x<<)+ch-'';ch=getchar();}

     return x*f;

 }

 int n,m,ans;

 int deg[];

 int main()

 {

     n=read(),m=read();

     for (int i=;i<=m;i++)

     {

         int x=read(),y=read();

         deg[x]++,deg[y]++;

     }

     for (int i=;i<=n;i++)ans+=(deg[i]*(n--deg[i]));

     printf("%d\n",n*(n-)*(n-)/-ans/);

 }