Encoding a sentence into Pig Latin

Design a program to take a sentence as an input, and then encode it into Pig Latin. 
 

A Pig Latin is an encrypted word in English, generated by placing the first letter of each word at the end, and then adding "ay" to the end.

Examples:

Input: s = "nevermind youve got them"
Output: "evermindnay ouveyay otgay hemtay"

Input: s = "sally knows best"
Output: "allysay nowskay estbay"

Approach: The problem can be solved by traversing the sentence and making the changes word by word, as follows:

1. Find the index of the first letter of the word.
2. Create a Pig Latin by appending the following these steps:
   • Append the first letter at the end of the substring of the word.
   • Add "ay" after appending the first letter.
3. Continue the above steps till the last word in the string.

Below is the java program to implement the approach:

allysay nowskay estbay

Time Complexity: O(N), where N is the length of sentence 
Auxiliary Space: O(N)