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 Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
int[]	prevPermOpt1(int[] arr)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

prevPermOpt1

public int[] prevPermOpt1(int[] arr)