#include <iostream>
#include <queue>
using namespace std;

int maze[1005][1005] = {0};
int used[1005][1005] = {0};
int dcol[] = {0, 1, 0, -1};
int drow[] = {-1, 0, 1, 0};

int main() {
	int n, m;
	cin >> n >> m;
	for (int row = 0; row < n; ++row) {
		string temp;
		cin >> temp;
		int index = 0;
		for (auto col: temp) {
			maze[row][index] = col - '0';
			++index;
		}
	}
	for (int t = 0; t < m; ++t) {
		// start querying
		int start_row, start_col;
		cin >> start_row >> start_col;
		--start_row;
		--start_col;
		// bfs
		int count = 0;
		queue<int> q;
		q.push(start_row);
		q.push(start_col);
		while (!q.empty()) {
			int row = q.front();
			q.pop();
			int col = q.front();
			q.pop();
			if (used[row][col]) continue;
			else used[row][col] = 1;
			//cout << row<< col << " endl" << endl;
			++count;
			for (int i = 0; i < 4; ++i) {
				int new_row = row+drow[i];
				int new_col = col+dcol[i];
				if (new_row < 0 || new_col < 0 || new_row >= n || new_col >= n) {
					continue;
			    }
			    if (maze[new_row][new_col] != maze[row][col]) {		
					q.push(new_row);
					q.push(new_col);
				}
			}
		}
		cout << count << endl;
		for (int i = 0; i < n; ++i) {
			for (int j = 0; j < n; ++j) {
				used[i][j] = 0;
			}
		}
	}
	/*for (int i = 0; i < n; ++i) {
		for (int j = 0; j < n; ++j) {
			cout << maze[i][j] << " ";
		}
		cout << endl;
	}*/
}

[https://www.luogu.com.cn/record/78541706]