https://leetcode.com/contest/weekly-contest-60/problems/flood-fill/

class Solution {
private:
        int h;
        int w;
        inline bool top(int sr, int sc, pair<int, int> &result) {
            if (sr > 0) {
                result = make_pair((sr - 1), sc);
                return true;
            }
            return false;
        }
        inline bool down(int sr, int sc, pair<int, int> &result) {
            if (sr < (h - 1)) {
                result = make_pair((sr + 1), sc);
                return true;
            }
            return false;
        }
        inline bool left(int sr, int sc, pair<int, int> &result) {
            if (sc > 0) {
                result = make_pair(sr, (sc - 1));
                return true;
            }
            return false;
        }
        inline bool right(int sr, int sc, pair<int, int> &result) {
            if (sc < (w - 1)) {
                result = make_pair(sr, sc + 1);
                return true;
            }
            return false;
        }
public:
    vector<vector<int>> floodFill(vector<vector<int>>& image, int sr, int sc, int newColor) {
        h = image.size();
        w = image[0].size();
        vector<vector<bool>> visit(h, vector<bool>(w, false));

        queue<pair<int, int> > q;
        int color = image[sr][sc];
        image[sr][sc] = newColor;
        visit[sr][sc] = true;
        q.push(make_pair(sr,sc));

        int count = 0;
        while (!q.empty() && (count++ < 10)) {
            pair<int, int> now = q.front();
            q.pop();
            pair<int, int> neighbor;
            if (top(now.first, now.second, neighbor)) {
                if (!visit[neighbor.first][neighbor.second] && (image[neighbor.first][neighbor.second] == color)) {
                    q.push(neighbor);
                    visit[neighbor.first][neighbor.second] = true;
                    image[neighbor.first][neighbor.second] = newColor;
                }
            }
            if (down(now.first, now.second, neighbor)) {
                if (!visit[neighbor.first][neighbor.second] && (image[neighbor.first][neighbor.second] == color)) {
                    q.push(neighbor);
                    visit[neighbor.first][neighbor.second] = true;
                    image[neighbor.first][neighbor.second] = newColor;
                }
            }
            if (left(now.first, now.second, neighbor)) {
                if (!visit[neighbor.first][neighbor.second] && (image[neighbor.first][neighbor.second] == color)) {
                    q.push(neighbor);
                    visit[neighbor.first][neighbor.second] = true;
                    image[neighbor.first][neighbor.second] = newColor;
                }
            }
            if (right(now.first, now.second, neighbor)) {
                if (!visit[neighbor.first][neighbor.second] && (image[neighbor.first][neighbor.second] == color)) {
                    q.push(neighbor);
                    visit[neighbor.first][neighbor.second] = true;
                    image[neighbor.first][neighbor.second] = newColor;
                }
            }
        }
        return image;
    }
};