Package g0701_0800.s0778_swim_in_rising_water

Class Solution

java.lang.Object
g0701_0800.s0778_swim_in_rising_water.Solution
public class Solution extends java.lang.Object
778 - Swim in Rising Water.

Hard

You are given an n x n integer matrix grid where each value grid[i][j] represents the elevation at that point (i, j).

The rain starts to fall. At time t, the depth of the water everywhere is t. You can swim from a square to another 4-directionally adjacent square if and only if the elevation of both squares individually are at most t. You can swim infinite distances in zero time. Of course, you must stay within the boundaries of the grid during your swim.

Return the least time until you can reach the bottom right square (n - 1, n - 1) if you start at the top left square (0, 0).

Example 1:

Input: grid = [[0,2],[1,3]]

Output: 3

Explanation:

 At time 0, you are in grid location (0, 0).
 You cannot go anywhere else because 4-directionally adjacent neighbors have a higher elevation than t = 0.
 You cannot reach point (1, 1) until time 3.
 When the depth of water is 3, we can swim anywhere inside the grid.

Example 2:

Input: grid = [[0,1,2,3,4],[24,23,22,21,5],[12,13,14,15,16],[11,17,18,19,20],[10,9,8,7,6]]

Output: 16

Explanation:

 The final route is shown.
 We need to wait until time 16 so that (0, 0) and (4, 4) are connected.

Constraints:

  • n == grid.length
  • n == grid[i].length
  • 1 <= n <= 50
  • 0 <= grid[i][j] < n2
  • Each value grid[i][j] is unique.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    bfs(int[][] grid, int limit)
     
    int
    swimInWater(int[][] grid)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • swimInWater

      public int swimInWater(int[][] grid)

    • bfs

      public boolean bfs(int[][] grid, int limit)