#include<iostream>
#include<cstring>
#include<queue>
using namespace std;
const int N=1010;
int dist[N][N];
bool st[N][N];
char g[N][N];
typedef pair<int,int> PP;
int n,m;
int map[N][N];
int dx[4]={0,-1,0,1};
int dy[4]={-1,0,1,0};
int num;
int ans[N*N];
void bfs(int a,int b)
{
    memset(dist,0,sizeof dist);
    memset(st,0,sizeof st);
    dist[a][b]=1;
    num++;
    map[a][b]=num;
    queue<PP> q;
    q.push({a,b});
    
    while(!q.empty())
    {
        PP t=q.front();
        q.pop();
        int x=t.first,y=t.second;
        for(int i=0;i<4;i++)
        {
            int xx=x+dx[i],yy=y+dy[i];
            if(xx<1||xx>n||yy<1||yy>n)continue;
            if(map[xx][yy])continue;
            if(g[xx][yy]==g[x][y])continue;
            
            dist[a][b]++;
            map[xx][yy]=num;
            
            q.push({xx,yy});
            
        }
    }
    ans[num]=dist[a][b];
}
int main()
{
    cin>>n>>m;
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
        {
            cin>>g[i][j];
        }
    }
    while(m--)
    {
        int a,b;
        cin>>a>>b;
        if(map[a][b]==0)
        {
            bfs(a,b);
            cout<<dist[a][b]<<endl;
        }
        else
        {
            cout<<ans[map[a][b]]<<endl;
        }
    }
}