Pacific Atlantic Water Flow
MediumP3Coding
A rectangular island is described by a grid heights. The Pacific ocean touches the top and left edges; the Atlantic touches the bottom and right edges. Rain on a cell flows to an adjacent cell (up, down, left or right) whose height is less than or equal to its own, and it can flow into an ocean from any edge cell that borders it.
Return the coordinates [row, col] of every cell from which water can reach both oceans. The pairs may be returned in any order.
Example 1
- Input
- heights = [[1,2,3],[8,9,4],[7,6,5]]
- Output
- [[0,2],[1,0],[1,1],[1,2],[2,0],[2,1],[2,2]]
Example 2
- Input
- heights = [[1]]
- Output
- [[0,0]]
Constraints
- 1 <= rows, cols <= 200
- 0 <= heights[i][j] <= 10^5
Hints
Give it a real attempt first. Run shows which examples fail.
Saved automatically
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