#include<bits/stdc++.h>
#define MAXN 2007
using namespace std;
const int mod=1e9+7;
int n,m,a,b,ans;
int dp[MAXN][MAXN][30];
bool li[MAXN][MAXN][30];
int cnt[MAXN],pref[MAXN],cnt2[MAXN],pref2[MAXN];
int maxs[MAXN][MAXN],maxs2[MAXN][MAXN],es[MAXN],es2[MAXN];
bool open(int l,int r){
return maxs[l][r]>=r;
}
bool open2(int l,int r){
return maxs2[l][r]>=r;
}
int ff(int pos,int change,int last){
if(pos==n+1)return 1;
if(li[pos][change][last])return dp[pos][change][last];
li[pos][change][last]=true;
if(last!=26)dp[pos][change][last]=ff(pos+1,change,last);
for(int i=0;i<26;i++){
if(i==last)continue;
if(i<last and open(change+1,pos))continue;
if(i>last and open2(change+1,pos))continue;
dp[pos][change][last]+=ff(pos+1,pos,i);
dp[pos][change][last]%=mod;
}
return dp[pos][change][last];
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin>>n>>m;
for(int i=1;i<=m;i++){
cin>>a>>b;
if(a<b){
cnt[a+1]++;
es[a+1]=max(es[a+1],b);
pref[a+1]++; pref[b+1]--;
}else{
cnt2[b+1]++;
es2[b+1]=max(es2[b+1],a);
pref2[b+1]++; pref2[a+1]--;
}
}
for(int i=1;i<=n;i++){
for(int f=i;f<=n;f++){
maxs[i][f]=max(maxs[i][f-1],es[f]);
maxs2[i][f]=max(maxs2[i][f-1],es2[f]);
}
}
cout<<ff(1,0,26)<<"\n";
return 0;
}
