1 #include <cstdio>
 2 #include <iostream>
 3 #include <algorithm>
 4 #define ll long long
 5 using namespace std;
 6 const int N=100010,mo=1e9+7;
 7 int n,c;
 8 ll f[N],g[N],fac[2*N],ny[2*N],r;
 9 struct edge { ll x,y; }a[N];
10 ll ksm(ll a,ll b) { for (r=1;b;b>>=1,a=a*a%mo) if (b&1) r=r*a%mo; return r; }
11 ll C(int b,int a) 
12 { 
13     if (a==0||a==b) return 1;
14     return ((fac[b]*ny[a])%mo*ny[b-a])%mo; 
15 }
16 bool cmp(edge a,edge b) { return a.x<b.x||a.x==b.x&&a.y<b.y; }
17 ll calc(int i,int j)
18 {
19     int x=a[j].x-a[i].x,y=a[j].y-a[i].y;
20     if (x<0||y<0) return 0;
21     if (a[j].y-1-a[i].x<0||a[j].x+1-a[i].y<0) return C(x+y,x);
22     return (C(x+y,x)-C(x+y,a[j].y-1-a[i].x)+mo)%mo;
23 }
24 int main()
25 {
26     scanf("%d%d",&n,&c);
27     for (int i=1;i<=c;i++) scanf("%d%d",&a[i].x,&a[i].y);
28     fac[1]=ny[1]=1; for (int i=2;i<=n*2;i++) fac[i]=(fac[i-1]*i)%mo,ny[i]=ksm(fac[i],mo-2);
29     a[c+1].x=n,a[c+1].y=n,sort(a,a+c+1,cmp);
30     for (int i=1;i<=c+1;i++)
31     {
32         for (int j=1;j<i;j++) (g[i]+=f[j]*calc(j,i)%mo)%=mo;
33         f[i]=(calc(0,i)-g[i]+mo)%mo;
34     }
35     printf("%lld",f[c+1]);
36 }