In a 2D grid of 0s and 1s, we change at most one 0 to a 1.
After, what is the size of the largest island?(An island is a 4-directionally connected group of 1s).
Example 1:
Input: [[1, 0], [0, 1]]
Output: 3
Explanation: Change one 0 to 1 and connect two 1s, then we get an island with area = 3.
Example 2:
Input: [[1, 1], [1, 0]]
Output: 4
Explanation: Change the 0 to 1 and make the island bigger, only one island with area = 1.
Example 3:
Input: [[1, 1], [1, 1]]
Output: 4
Explanation: Can't change any 0 to 1, only one island with area = 1.
Notes:
- 1 <= grid.length = grid[0].length <= 50.
- 0 <= grid[i][j] <= 1.
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