Package g1301_1400.s1370_increasing_decreasing_string

Class Solution

java.lang.Object
g1301_1400.s1370_increasing_decreasing_string.Solution
public class Solution extends java.lang.Object
1370 - Increasing Decreasing String.

Easy

You are given a string s. Reorder the string using the following algorithm:

  1. Pick the smallest character from s and append it to the result.
  2. Pick the smallest character from s which is greater than the last appended character to the result and append it.
  3. Repeat step 2 until you cannot pick more characters.
  4. Pick the largest character from s and append it to the result.
  5. Pick the largest character from s which is smaller than the last appended character to the result and append it.
  6. Repeat step 5 until you cannot pick more characters.
  7. Repeat the steps from 1 to 6 until you pick all characters from s.

In each step, If the smallest or the largest character appears more than once you can choose any occurrence and append it to the result.

Return the result string after sorting s with this algorithm.

Example 1:

Input: s = “aaaabbbbcccc”

Output: “abccbaabccba”

Explanation: After steps 1, 2 and 3 of the first iteration, result = “abc”

After steps 4, 5 and 6 of the first iteration, result = “abccba”

First iteration is done. Now s = “aabbcc” and we go back to step 1

After steps 1, 2 and 3 of the second iteration, result = “abccbaabc”

After steps 4, 5 and 6 of the second iteration, result = “abccbaabccba”

Example 2:

Input: s = “rat”

Output: “art”

Explanation: The word “rat” becomes “art” after re-ordering it with the mentioned algorithm.

Constraints:

  • 1 <= s.length <= 500
  • s consists of only lowercase English letters.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    java.lang.String
    sortString(java.lang.String s)
     

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • sortString

      public java.lang.String sortString(java.lang.String s)