Count Hills and Valleys in an Array LeetCode solution in Java

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class Solution {
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  public int countHillValley(int[] nums) {
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    int result = 0;
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    // Get head start. Find first index for which nums[index] != nums[index-1]
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    int start = 1;
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    while (start < nums.length && nums[start] == nums[start - 1]) start++;
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    int prev = start - 1; // index of prev different value num
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    for (int i = start; i < nums.length - 1; i++) {
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      if (nums[i] == nums[i + 1]) // If numbers are same, simply ignore them
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      continue;
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      else {
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        if (nums[i] > nums[prev]
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            && nums[i] > nums[i + 1]) // compare current num with prev number and next number
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        result++;
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        if (nums[i] < nums[prev] && nums[i] < nums[i + 1]) result++;
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        prev = i; // Now your current number will become prev number.
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      }
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    }
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    return result;
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  }
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}