Find All Groups of Farmland LeetCode solution in C++

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class Solution {
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 public:
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  vector<vector<int>> nbrs = {{0, 1}, {1, 0}, {-1, 0}, {0, -1}};
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  pair<int, int> dfs(vector<vector<int>> &land, int i, int j, vector<vector<bool>> &visited) {
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    visited[i][j] = true;
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    pair<int, int> res = make_pair(i, j);
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    for (auto &nbr : nbrs) {
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      int x = i + nbr[0];
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      int y = j + nbr[1];
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      if (x < 0 || y < 0 || x >= land.size() || y >= land[0].size() || visited[x][y] ||
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          land[x][y] != 1)
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        continue;
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      pair<int, int> ans = dfs(land, x, y, visited);
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      res.first = max(res.first, ans.first);
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      res.second = max(res.second, ans.second);
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    }
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    return res;
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  }
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  vector<vector<int>> findFarmland(vector<vector<int>> &land) {
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    int m = land.size();
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    int n = land[0].size();
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    vector<vector<bool>> visited(m, vector<bool>(n, false));
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    vector<vector<int>> ans;
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    for (int i = 0; i < m; i++) {
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      for (int j = 0; j < n; j++) {
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        if (!visited[i][j] && land[i][j] == 1) {
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          pair<int, int> p = dfs(land, i, j, visited);
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          vector<int> res;
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          res.push_back(i);
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          res.push_back(j);
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          res.push_back(p.first);
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          res.push_back(p.second);
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          ans.push_back(res);
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          cout << 1 << endl;
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        }
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      }
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    }
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    return ans;
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  }
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};