Next Permutation LeetCode solution in Java

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class Solution {
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  public void nextPermutation(int[] nums) {
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    // FIND peek+1
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    int nextOfPeak = -1;
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    for (int i = nums.length - 1; i > 0; i--) {
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      if (nums[i] > nums[i - 1]) {
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        nextOfPeak = i - 1;
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        break;
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      }
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    }
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    // Return reverse Array
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    if (nextOfPeak == -1) {
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      int start = 0;
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      int end = nums.length - 1;
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      while (start <= end) {
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        int temp = nums[start];
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        nums[start] = nums[end];
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        nums[end] = temp;
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        start++;
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        end--;
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      }
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      return;
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    }
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    // Find element greater than peek
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    int reversalPoint = nums.length - 1;
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    for (int i = nums.length - 1; i > nextOfPeak; i--) {
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      if (nums[i] > nums[nextOfPeak]) {
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        reversalPoint = i;
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        break;
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      }
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    }
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    // swap nextOfPeak && reversalPoint
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    int temp = nums[nextOfPeak];
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    nums[nextOfPeak] = nums[reversalPoint];
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    nums[reversalPoint] = temp;
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    // Reverse array from nextOfPeak+1
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    int start = nextOfPeak + 1;
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    int end = nums.length - 1;
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    while (start <= end) {
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      int temp1 = nums[start];
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      nums[start] = nums[end];
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      nums[end] = temp1;
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      start++;
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      end--;
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    }
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  }
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}