leetcode

0 class Solution {

1 public:

2 int findMaxFish(vector<vector<int>> &grid) const {

3 static const int offset[] = {1, 0, -1, 0, 1};

4 const int n = grid.size(), m = grid[0].size();

5 const auto valid = [n, m](int x, int y) { return x >= 0 && x < n && y >= 0 && y < m; };

6 int res = 0;

7 for (int i = 0; i < n; i++) {

8 for (int j = 0; j < m; j++) {

9 if (!grid[i][j]) continue;

10 int count = grid[i][j];

11 grid[i][j] = 0;

12

13 queue<pair<int, int>> q;

14 q.push({i, j});

15 while (!q.empty()) {

16 const auto [a, b] = q.front();

17 for (int k = 0; k < 4; k++) {

18 const int x = a + offset[k];

19 const int y = b + offset[k + 1];

20 if (!valid(x, y)) continue;

21 if (!grid[x][y]) continue;

22 count += grid[x][y];

23 grid[x][y] = 0;

24 q.push({x, y});

25 }

26 q.pop();

27 }

28 res = max(res, count);

29 }

30 }

31 return res;

32 }

33 };