add 1 without + operator done

Author: Ram swaroop

src/me/ramswaroop/bits/Addition.java

@@ -0,0 +1,39 @@
+package me.ramswaroop.bits;
+
+/**
+ * Created by IntelliJ IDEA.
+ *
+ * @author: ramswaroop
+ * @date: 6/10/15
+ * @time: 12:55 PM
+ */
+public class Addition {
+
+    /**
+     * Idea is to flip all the bits of {@param n} till
+     * rightmost 0 bit in {@param n}.
+     *
+     * @param n
+     * @return
+     */
+    public static int add1(int n) {
+        int mask = 1;
+        // flip all bits in n until rightmost 0 bit
+        while ((n & mask) != 0) {
+            n ^= mask;
+            mask <<= 1;
+        }
+        // flip the rightmost 0 bit
+        return n ^ mask;
+    }
+
+    public static void main(String a[]) {
+        System.out.println(add1(0));
+        System.out.println(add1(1));
+        System.out.println(add1(2));
+        System.out.println(add1(3));
+        System.out.println(add1(4));
+        System.out.println(add1(5));
+        System.out.println(add1(7));
+    }
+}