#include
     
      #include
      
       #include
       
        #include
        
         #include
         
          #include
          
           #include
           
            bool f[1005][1005];char a[1005][1005];int dx[]={ 0,0,0,1,-1};int dy[]={ 0,1,-1,0,0};int n,m;int num[1009][1009];using namespace std;struct H{ int x; int y;}pos[1000*1000+100];int bfs(int kx,int ky){ int head=0,tail=1; if(!num[kx][ky]){ pos[head+1].x=kx,pos[head+1].y=ky;f[kx][ky]=true; while(head
            
             =1&&ny<=n&&ny>=1) if(a[nx][ny]!=a[pos[head].x][pos[head].y]&&!f[nx][ny]){ pos[++tail].x=nx;pos[tail].y=ny;f[nx][ny]=true; } } } for(int i=1;i<=tail;i++)num[pos[i].x][pos[i].y]=tail;//记忆化 } return num[kx][ky];}int main(){ scanf("%d%d",&n,&m); for(int i=1;i<=n;i++){ for(int j=1;j<=n;j++) cin>>a[i][j]; } for(int i=1;i<=m;i++){ //memset(f,false,sizeof(f));记忆化,不用memset,否则超时 int ax,ay; scanf("%d%d",&ax,&ay); printf("%d\n",bfs(ax,ay)); } return 0; }