Given an array of non-negative integers?arr, you are initially positioned at?start?index of the array. When you are at index?i, you can jump?to?i + arr[i]?or?i - arr[i], check if you can reach to?any?index with value 0.

Notice that you can not jump outside of the array at any time.

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Example 1:

Input: arr = [4,2,3,0,3,1,2], start = 5Output: trueExplanation: All possible ways to reach at index 3 with value 0 are: index 5 -> index 4 -> index 1 -> index 3 index 5 -> index 6 -> index 4 -> index 1 -> index 3

Example 2:

Input: arr = [4,2,3,0,3,1,2], start = 0Output: true Explanation: One possible way to reach at index 3 with value 0 is: index 0 -> index 4 -> index 1 -> index 3

Example 3:

Input: arr = [3,0,2,1,2], start = 2Output: falseExplanation: There is no way to reach at index 1 with value 0.

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Constraints:

• 1 <= arr.length <= 5 * 104

• 0 <= arr[i] <?arr.length

• 0 <= start < arr.length

典型的DFS;每次遞歸往里面查找；然后有個(gè)數(shù)組記錄是否查找過。

Runtime:?7 ms, faster than?45.27%?of?Java?online submissions for?Jump Game III.

Memory Usage:?62.2 MB, less than?34.88%?of?Java?online submissions for?Jump Game III.