Problem: You are given an integer sequence of length N: A_1,A_2,...,A_N. Let us perform Q operations in order. The i-th operation is described by two integers X_i and Y_i. In this operation, we will choose one of the following two actions and perform it:

* Swap the values of A_{X_i} and A_{Y_i}
* Do nothing



There are 2^Q ways to perform these operations. Find the sum of the inversion numbers of the final sequences for all of these ways to perform operations, modulo 10^9+7.

Here, the inversion number of a sequence P_1,P_2,...,P_M is the number of pairs of integers (i,j) such that 1\leq i < j\leq M and P_i > P_j.

Constraints

* 1 \leq N \leq 3000
* 0 \leq Q \leq 3000
* 0 \leq A_i \leq 10^9(1\leq i\leq N)
* 1 \leq X_i,Y_i \leq N(1\leq i\leq Q)
* X_i\neq Y_i(1\leq i\leq Q)
* All values in input are integers.

Input

Input is given from Standard Input in the following format:


N Q
A_1
:
A_N
X_1 Y_1
:
X_Q Y_Q


Output

Print the sum of the inversion numbers of the final sequences, modulo 10^9+7.

Examples

Input

3 2
1
2
3
1 2
1 3


Output

6


Input

5 3
3
2
3
1
4
1 5
2 3
4 2


Output

36


Input

9 5
3
1
4
1
5
9
2
6
5
3 5
8 9
7 9
3 2
3 8


Output

425

Solution (in CPP):

Solution:
#include<bits/stdc++.h>
#define ll long long
#define mod 1000000007
#define N 3009
using namespace std;

int n,m,a[N],f[N][N];
int main(){
	scanf("%d%d",&n,&m);
	int i,j,x,y,tmp;
	for (i=1; i<=n; i++) scanf("%d",&a[i]);
	for (i=1; i<=n; i++)
		for (j=1; j<=n; j++) f[i][j]=(a[i]<a[j]);
	int t=1;
	while (m--){
		t=t*2%mod;
		scanf("%d%d",&x,&y);
		for (i=1; i<=n; i++) if (i!=x && i!=y){
			tmp=(f[x][i]+f[y][i])%mod; tmp=(tmp&1)?(tmp+mod>>1):tmp>>1;
			f[x][i]=f[y][i]=tmp%mod;
			tmp=(f[i][x]+f[i][y])%mod; tmp=(tmp&1)?(tmp+mod>>1):tmp>>1;
			f[i][x]=f[i][y]=tmp%mod;
		}
		tmp=(f[x][y]+f[y][x])%mod; tmp=(tmp&1)?(tmp+mod>>1):tmp>>1;
		f[x][y]=f[y][x]=tmp%mod;
	}
	int ans=0;
	for (i=1; i<=n; i++)
		for (j=1; j<i; j++) ans=(ans+f[i][j])%mod;
	printf("%lld\n",(ll)ans*t%mod);
	return 0;
}