add Base solution for hw3

java/reverse/Reverse.java

@@ -0,0 +1,49 @@
+package reverse;
+
+import java.util.ArrayList;
+import java.util.Scanner;
+
+public class Reverse {
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+        ArrayList<ArrayList<String>> lines = new ArrayList<>();
+
+        while (sc.hasNextLine()) {
+            ArrayList<String> line = new ArrayList<>();
+            StringBuilder builder = new StringBuilder();
+            String lineString = sc.nextLine();
+
+            for (char c : lineString.toCharArray()) {
+                if (!Character.isWhitespace(c)) {
+                    builder.append(c);
+                } else {
+                    if (!builder.toString().isEmpty()) {
+                        line.add(builder.toString());
+                    }
+                    builder = new StringBuilder();
+                }
+            }
+            if (!builder.toString().isEmpty()) {
+                line.add(builder.toString());
+            }
+            lines.add(line);
+        }
+
+        sc.close();
+
+
+
+        for (int i = lines.size() - 1; i >= 0; i--) {
+            if (lines.get(i).isEmpty()) {
+                System.out.println();
+            }
+            for (int j = lines.get(i).size() - 1; j >= 0; j--) {
+                if (j > 0) {
+                    System.out.print(lines.get(i).get(j) + " ");
+                } else {
+                    System.out.println(lines.get(i).get(j));
+                }
+            }
+        }
+    }
+}