Given an array of integers
arr, you are initially positioned at the first index of the array.
In one step you can jump from index
i to index:
i + 1where:
i + 1 < arr.length.
i - 1where:
i - 1 >= 0.
arr[i] == arr[j]and
i != j.
Return the minimum number of steps to reach the last index of the array.
Notice that you can not jump outside of the array at any time.
Input: arr = [100,-23,-23,404,100,23,23,23,3,404] Output: 3 Explanation: You need three jumps from index 0 --> 4 --> 3 --> 9. Note that index 9 is the last index of the array.
Input: arr =  Output: 0 Explanation: Start index is the last index. You do not need to jump.
Input: arr = [7,6,9,6,9,6,9,7] Output: 1 Explanation: You can jump directly from index 0 to index 7 which is last index of the array.
1 <= arr.length <= 5 * 104
-108 <= arr[i] <= 108