Added 3rd program

Multi3.java

@@ -0,0 +1,10 @@
+class Multi3 implements Runnable {
+    public void run(){
+        System.out.println("thread is running..");
+    }    
+    public static void main(String[] args) {
+        Multi3 m1 = new Multi3();
+        Thread t1 = new Thread(m1);
+        t1.start();
+    }
+}

src/Title.txt

@@ -1,2 +1,3 @@
-1A. write a java code by extending thread class
-1B. write a java code 
+1. write a java code by extending thread class
+2. write a java code by implementing runnable interface.
+3.