import java.util.*; public class Solution { public String ReverseSentence(String str) { String[] ss = str.split(" "); Stack<String> st = new Stack<>(); StringBuilder sb = new StringBuilder(); for(String s : ss){ st.push(s); } while(!st.isEmpty()){ sb.append(st.pop()); sb.append(" "); } sb.deleteCharAt(sb.length() - 1); return sb.toString(); } }