#include using namespace std; #define repd(i,a,b) for (ll i=(a);i<(b);i++) #define rep(i,n) repd(i,0,n) #define all(x) (x).begin(),(x).end() template inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; } template inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; } typedef long long ll; typedef pair P; typedef vector vec; typedef vector Graph; const long long INF = 1LL<<60; const long long MOD = 1000000007; // auto mod int // https://youtu.be/L8grWxBlIZ4?t=9858 // https://youtu.be/ERZuLAxZffQ?t=4807 : optimize // https://youtu.be/8uowVvQ_-Mo?t=1329 : division const int mod = 100000007; struct mint { ll x; // typedef long long ll; mint(ll x=0):x((x%mod+mod)%mod){} mint operator-() const { return mint(-x);} mint& operator+=(const mint a) { if ((x += a.x) >= mod) x -= mod; return *this; } mint& operator-=(const mint a) { if ((x += mod-a.x) >= mod) x -= mod; return *this; } mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this;} mint operator+(const mint a) const { return mint(*this) += a;} mint operator-(const mint a) const { return mint(*this) -= a;} mint operator*(const mint a) const { return mint(*this) *= a;} mint pow(ll t) const { if (!t) return 1; mint a = pow(t>>1); a *= a; if (t&1) a *= *this; return a; } // for prime mod mint inv() const { return pow(mod-2);} mint& operator/=(const mint a) { return *this *= a.inv();} mint operator/(const mint a) const { return mint(*this) /= a;} }; istream& operator>>(istream& is, mint& a) { return is >> a.x;} ostream& operator<<(ostream& os, const mint& a) { return os << a.x;} // combination mod prime // https://www.youtube.com/watch?v=8uowVvQ_-Mo&feature=youtu.be&t=1619 struct combination { vector fact, ifact; combination(int n):fact(n+1),ifact(n+1) { assert(n < mod); fact[0] = 1; for (int i = 1; i <= n; ++i) fact[i] = fact[i-1]*i; ifact[n] = fact[n].inv(); for (int i = n; i >= 1; --i) ifact[i-1] = ifact[i]*i; } mint operator()(int n, int k) { if (k < 0 || k > n) return 0; return fact[n]*ifact[k]*ifact[n-k]; } mint p(int n,int k){ return fact[n]*ifact[n-k]; } } c(1000005); int main() { ios::sync_with_stdio(false); cin.tie(0); ll h,w,k; cin>>h>>w>>k; vec a(k),b(k); rep(i,k)cin>>a[i]>>b[i]; vector memo(1< v={P(0,0),P(h,w)}; rep(j,k){ if((i>>j)&1){ v.push_back({a[j],b[j]}); } } sort(all(v)); mint now=1; repd(j,1,v.size()){ auto[x,y]=v[j-1]; auto[z,w]=v[j]; x=z-x; y=w-y; if(y<0)now=0; else now*=c(x+y,x); } memo[i]=now; } repd(i,1,1<>i)&1){ ll x=j^(1<