Package g0401_0500.s0443_string_compression

Class Solution

java.lang.Object
g0401_0500.s0443_string_compression.Solution
public class Solution extends Object
443 - String Compression\. Medium Given an array of characters `chars`, compress it using the following algorithm: Begin with an empty string `s`. For each group of **consecutive repeating characters** in `chars`: * If the group's length is `1`, append the character to `s`. * Otherwise, append the character followed by the group's length. The compressed string `s` **should not be returned separately** , but instead, be stored **in the input character array `chars` **. Note that group lengths that are `10` or longer will be split into multiple characters in `chars`. After you are done **modifying the input array** , return _the new length of the array_. You must write an algorithm that uses only constant extra space. **Example 1:** **Input:** chars = ["a","a","b","b","c","c","c"] **Output:** Return 6, and the first 6 characters of the input array should be: ["a","2","b","2","c","3"] **Explanation:** The groups are "aa", "bb", and "ccc". This compresses to "a2b2c3". **Example 2:** **Input:** chars = ["a"] **Output:** Return 1, and the first character of the input array should be: ["a"] **Explanation:** The only group is "a", which remains uncompressed since it's a single character. **Example 3:** **Input:** chars = ["a","b","b","b","b","b","b","b","b","b","b","b","b"] **Output:** Return 4, and the first 4 characters of the input array should be: ["a","b","1","2"]. **Explanation:** The groups are "a" and "bbbbbbbbbbbb". This compresses to "ab12". **Example 4:** **Input:** chars = ["a","a","a","b","b","a","a"] **Output:** Return 6, and the first 6 characters of the input array should be: ["a","3","b","2","a","2"]. **Explanation:** The groups are "aaa", "bb", and "aa". This compresses to "a3b2a2". Note that each group is independent even if two groups have the same character. **Constraints:** * `1 <= chars.length <= 2000` * `chars[i]` is a lowercase English letter, uppercase English letter, digit, or symbol.

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • compress

      public int compress(char[] chars)