1var findFarmland = function(land) {
2    const m = land.length;
3    const n = land[0].length;
4    const visited = Array.from({ length: m }, () => Array(n).fill(false));
5    const results = [];
6
7    function bfs(row, col) {
8        const queue = [[row, col]];
9        let maxRow = row, maxCol = col;
10        visited[row][col] = true;
11
12        while (queue.length) {
13            const [r, c] = queue.shift();
14            maxRow = Math.max(maxRow, r);
15            maxCol = Math.max(maxCol, c);
16
17            const directions = [[0, 1], [1, 0]];
18            for (const [dr, dc] of directions) {
19                const newRow = r + dr, newCol = c + dc;
20                if (newRow < m && newCol < n && land[newRow][newCol] === 1 && !visited[newRow][newCol]) {
21                    visited[newRow][newCol] = true;
22                    queue.push([newRow, newCol]);
23                }
24            }
25        }
26        results.push([row, col, maxRow, maxCol]);
27    }
28
29    for (let i = 0; i < m; i++) {
30        for (let j = 0; j < n; j++) {
31            if (land[i][j] === 1 && !visited[i][j]) {
32                bfs(i, j);
33            }
34        }
35    }
36
37    return results;
38};

using System.Collections.Generic;

public class Solution {
    public int[][] FindFarmland(int[][] land) {
        int m = land.Length, n = land[0].Length;
        int[] parent = new int[m * n];
        int[] rank = new int[m * n];

        for (int i = 0; i < m * n; i++) {
            parent[i] = i;
        }

        int Find(int x) {
            if (parent[x] != x) {
                parent[x] = Find(parent[x]);
            }
            return parent[x];
        }

        void Union(int x, int y) {
            int rootX = Find(x);
            int rootY = Find(y);
            if (rootX != rootY) {
                if (rank[rootX] > rank[rootY]) {
                    parent[rootY] = rootX;
                } else if (rank[rootX] < rank[rootY]) {
                    parent[rootX] = rootY;
                } else {
                    parent[rootY] = rootX;
                    rank[rootX]++;
                }
            }
        }

        for (int i = 0; i < m; i++) {
            for (int j = 0; j < n; j++) {
                if (land[i][j] == 1) {
                    int index = i * n + j;
                    if (i > 0 && land[i-1][j] == 1) {
                        Union(index, (i-1) * n + j);
                    }
                    if (j > 0 && land[i][j-1] == 1) {
                        Union(index, i * n + (j-1));
                    }
                }
            }
        }

        var bounds = new Dictionary<int, int[]>();
        for (int i = 0; i < m; i++) {
            for (int j = 0; j < n; j++) {
                if (land[i][j] == 1) {
                    int root = Find(i * n + j);
                    if (!bounds.ContainsKey(root)) {
                        bounds[root] = new int[] { i, j, i, j };
                    } else {
                        bounds[root][0] = Math.Min(bounds[root][0], i);
                        bounds[root][1] = Math.Min(bounds[root][1], j);
                        bounds[root][2] = Math.Max(bounds[root][2], i);
                        bounds[root][3] = Math.Max(bounds[root][3], j);
                    }
                }
            }
        }

        var result = new List<int[]>(bounds.Values); 
        return result.ToArray();
    }
}