Red Huang

//====================================================================||  
//                                                                    ||  
//                                                                    ||  
//                         Author : GCA                               ||  
//                  6AE7EE02212D47DAD26C32C0FE829006                  ||  
//====================================================================||  
#include <iostream>  
#include <cstdio>  
#include <cstring>  
#include <algorithm>  
#include <cmath>  
#include <climits>  
#include <vector>  
#include <set>  
#include <map>  
#include <queue>  
#include <cctype>  
#include <utility>  
using namespace std;  
#ifdef ONLINE\_JUDGE  
#define ll "%lld"  
#else  
#define ll "%I64d"  
#endif  
typedef unsigned int uint;  
typedef long long int Int;  
#define Set(a,s) memset(a,s,sizeof(a))  
#define Write(w) freopen(w,"w",stdout)  
#define Read(r) freopen(r,"r",stdin)  
#define Pln() printf("\\n")  
#define I\_de(x,n)for(int i=0;i<n;i++)printf("%d ",x\[i\]);Pln()  
#define De(x)printf(#x"%d\\n",x)  
#define For(i,x)for(int i=0;i<x;i++)  
#define CON(x,y) x##y  
#define Pmz(dp,nx,ny)for(int hty=0;hty<ny;hty++){for(int htx=0;htx<nx;htx++){\\  
    printf("%2d ",dp\[htx\]\[hty\]);}Pln();}  
#define M 105  
#define PII pair<int,int\>  
#define PB push\_back  
#define oo INT\_MAX  
#define Set\_oo 0x3f  
#define Is\_debug true  
#define debug(...) if(Is\_debug)printf("DEBUG: "),printf(\_\_VA\_ARGS\_\_)  
#define FOR(it,c) for(\_\_typeof((c).begin()) it=(c).begin();it!=(c).end();it++)  
#define eps 1e-6  
bool xdy(double x,double y){return x>y+eps;}  
bool xddy(double x,double y){return x>y-eps;}  
bool xcy(double x,double y){return x<y-eps;}  
bool xcdy(double x,double y){return x<y+eps;}  
int min3(int x,int y,int z){  
    int tmp=min(x,y);  
    return min(tmp,z);  
}  
int max3(int x,int y,int z){  
    int tmp=max(x,y);  
    return max(tmp,z);  
}  
int w,h;  
int n;  
int mz\[M\]\[M\];  
Int used\[M\]\[M\];  
int dx\[2\]={0,1};  
int dy\[2\]={1,0};  
bool inq\[M\]\[M\];  
struct node{  
    int x,y;  
    node(int x,int y):x(x),y(y){};  
    node(){};  
};  
void solve(){  
    Set(inq,0);  
    Set(used,0);  
    queue<node> q;  
    q.push(node(0,0));  
    used\[0\]\[0\]=1;  
    inq\[0\]\[0\]=1;  
    while(!q.empty()){  
///        for(int i=0;i<=h;i++){  
///            for(int j=0;j<=w;j++){  
///                printf("%2d ",used\[j\]\[i\]);  
///            }Pln();  
///        }Pln();  
        int x=q.front().x;  
        int y=q.front().y;  
        q.pop();  
        Int u=used\[x\]\[y\];  
        for(int i=0;i<2;i++){  
            int nex=x+dx\[i\],ney=y+dy\[i\];  
            if(nex<0||nex>w||ney<0||ney>h)continue;  
            if(mz\[nex\]\[ney\])continue;  
            used\[nex\]\[ney\]+=u;  
            if(!inq\[nex\]\[ney\]){  
                inq\[nex\]\[ney\]=1;  
                q.push(node(nex,ney));  
            }  
        }  
        inq\[x\]\[y\]=0;  
    }  
    if(used\[w\]\[h\]==1){  
        printf("赤ずきんの家からおばあさんの家への道は1つあります。\\n");  
    }else if(used\[w\]\[h\]==0){  
        printf("道はありません。\\n");  
    }else{  
        printf("赤ずきんの家からおばあさんの家への道は%lldあります。\\n"  
                ,used\[w\]\[h\]);  
    }  
}  
int main(){  
//    freopen("input.txt","r",stdin);  
    ios\_base::sync\_with\_stdio(0);  
    while(~scanf("%d%d",&w,&h)&&w+h){  
        scanf("%d",&n);  
        Set(mz,0);  
        for(int i=0;i<n;i++){  
            int x,y;  
            scanf("%d%d",&x,&y);  
            mz\[x\]\[y\]=1;  
        }  
        solve();  
    }  
  
  
  
      
  
  
  
  
  
  
  
}