#include <stdio.h>
#include<vector>
#include <algorithm>
#include <map>
using namespace std;
typedef long long ll;
const int MX = 200005, MM = 1000000007;
ll pw(ll A, ll B){
ll R = 1;
while(B){
if( B&1 ) R = R * A % MM;
A = A * A % MM; B /= 2;
}
return R;
}
ll rv(ll A){ return pw(A, MM-2); }
struct frac{
ll A, B;
frac(ll A):A(A), B(1){}
frac(ll a, ll b){
A = (a%MM+MM) % MM;
B = (b%MM+MM) % MM;
}
frac(){A = 0, B = 1;}
frac operator+ (const frac &l)const{
return frac((A * l.B + B * l.A) % MM, B * l.B % MM);
}
frac operator*(const frac &l)const{
return frac(A*l.A % MM, B*l.B % MM);
}
frac operator/(const frac &l)const{
return frac(A*l.B % MM, B*l.A % MM);
}
frac operator- (const frac &l)const{
return frac((A*l.B - B*l.A%MM + MM) % MM, B*l.B % MM);
}
ll v(){ return A * rv(B) % MM; }
};
map<int, int> label;
struct UF{
int p[MX], cnt[MX];
UF(){ fill(cnt, cnt+MX, 1); }
int find(int x){ return !p[x]? x : p[x] = find(p[x]); }
int merge(int x, int y){
x = find(x), y = find(y);
if( x == y ) return false;
p[x] = y;
cnt[y] += cnt[x];
return true;
}
}uf;
int main()
{
int N, M, cnt = 0;
scanf("%d%d", &N, &M);
for(int i = 1; i <= M; i++){
int A, B;
scanf("%d%d", &A, &B);
if( label[A] == 0 ) label[A] = ++cnt;
if( label[B] == 0 ) label[B] = ++cnt;
A = label[A], B = label[B];
if( !uf.merge(A, B) ) return !printf("0");
}
frac ans = 1, tot = 0;
for(int i = 1; i <= cnt; i++){
if( i == uf.find(i) ) ans = ans * uf.cnt[i];
}
ans = ans * pw(N, N-M-2);
if(M+1 == N) return !printf("1");
printf("%lld\n", ans.v());
}
