1859. Sorting the Sentence

A sentence is a list of words that are separated by a single space with no leading or trailing spaces. Each word consists of lowercase and uppercase English letters.

A sentence can be shuffled by appending the 1-indexed word position to each word and then rearranging the words in the sentence.

• For example, the sentence "This is a sentence" can be shuffled as "sentence4 a3 is2 This1" or "is2 sentence4 This1 a3".

Given a shuffled sentence s containing no more than 9 words, reconstruct and return the original sentence.

Example 1:

Input: s = "is2 sentence4 This1 a3"
Output: "This is a sentence"
Explanation: Sort the words in s to their original positions "This1 is2 a3 sentence4", then remove the numbers.

Example 2:

Input: s = "Myself2 Me1 I4 and3"
Output: "Me Myself and I"
Explanation: Sort the words in s to their original positions "Me1 Myself2 and3 I4", then remove the numbers.

Constraints:

• 2 <= s.length <= 200

• s consists of lowercase and uppercase English letters, spaces, and digits from 1 to 9.

• The number of words in s is between 1 and 9.

• The words in s are separated by a single space.

• s contains no leading or trailing spaces.

LeetCode Solution Link

CODE:

public class SortingSentence {
  public static void main(String[] args) {
    String s = "is2 sentence4 This1 a3";
    String[] str = s.split(" ");
    int len = str.length;
    String[] result = new String[len];
    StringBuilder sb = new StringBuilder();
    int index =0;
    for(String string:str){
      int l = string.length();
      index = (int)(string.charAt(l-1)-'0');
      result[index-1] = string.substring(0, l-1);
    }

    for(int i=0; i<result.length-1; i++){
      sb.append(result[i]).append(" ");
    }
    sb.append(result[result.length-1]);

    System.out.println(sb.toString());
  }
}

This is a sentence

Explanation:

step 1:

split the string into a string array.

String[] str = s.split(" ");

s = "is2 sentence4 This1 a3"

str = [ "is2", "sentence4", "This1", "a3" ]

for finding the length of the string array is calculated using the len = str.length;

int index = 0;
for(String string:str){
      int l = string.length();
      index = (int)(string.charAt(l-1)-'0');
      result[index-1] = string.substring(0, l-1);
 }

for(String string:str) => It will directly take the string

string = "is2" => Here extract the number from the string.

"is2".length() -> l = 3

index = (int) (string.charAt(l-1) - '0')

unicode of '0' = 48

public class UnicodeExample {
    public static void main(String[] args) {
        char digitTwo = '0';

        // Getting the Unicode value
        int unicodeValue = (int) digitTwo;

        System.out.println("Unicode value of '0': " + unicodeValue);
    }
}

Unicode value of '0': 48

Unicode of '0' = 48

Unicode of '1' = 49

Unicode of '2' = 50

Unicode of '3' = 51 ........

index = (int) (string.charAt(3-1) - '0') => (int) ( '2'-'0' ) => 50-48 => index = 2

int[] result = new int[len];

result[index-1] = str.substring(0,l-1);

result[1] = is

result[3] = sentence

result[0] = This

result[2] = a

StringBuilder sb = new StringBuilder();
for(int i=0; i<result.length-1; i++){
      sb.append(result[i]).append(" ");
    }
    sb.append(result[result.length-1]);

i=0 => sb.append(0).append(" ") => sb = This

i=1 => sb.append(1) => sb = This is

i=2 => sb.append(2) => sb = This is a

3 < 3 condition false loop terminate. If we add the last word the extra space is added at the end.

sb.append(result[3]) => This is a sentence

sb.toString() => "This is a sentence".

Thank you for reading.

Happy Coding :)