Package g1001_1100.s1053_previous_permutation_with_one_swap

Class Solution

java.lang.Object
g1001_1100.s1053_previous_permutation_with_one_swap.Solution
public class Solution extends Object
1053 - Previous Permutation With One Swap.

Medium

Given an array of positive integers arr (not necessarily distinct), return the lexicographically largest permutation that is smaller than arr, that can be made with exactly one swap (A swap exchanges the positions of two numbers arr[i] and arr[j]). If it cannot be done, then return the same array.

Example 1:

Input: arr = [3,2,1]

Output: [3,1,2]

Explanation: Swapping 2 and 1.

Example 2:

Input: arr = [1,1,5]

Output: [1,1,5]

Explanation: This is already the smallest permutation.

Example 3:

Input: arr = [1,9,4,6,7]

Output: [1,7,4,6,9]

Explanation: Swapping 9 and 7.

Constraints:

  • 1 <= arr.length <= 104
  • 1 <= arr[i] <= 104

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • prevPermOpt1

      public int[] prevPermOpt1(int[] arr)