1. Splitting and reversing a sentence a word by word
class Solution { public String reverseWords(String s) { s = s.trim(); String[] split = s.split("\\s+"); String rever = ""; int pointer = split.length - 1; rever = rever + split[pointer]; pointer--; while(pointer >= 0){ rever = rever + " " + split[pointer]; pointer--; } return rever; }//reverseWords method }