adding the power-of-2 algorithm (bitwisebitwise-manipulation)

algorithms/bit-manipulation/power-of-2.c

@@ -0,0 +1,42 @@
+/**
+ * power of 2 algorithm
+ * check wether a given integer n 
+ * can be in a put in a form of power of 2
+ * by using a bitwise manipulation 
+ * Time compexity = O(n)
+ * example : n = 16 can be put in the form 2^4
+ */
+
+int power_of_two(int n){
+    /* for edge cases */
+    if(n <= 0) return 0;
+
+    if ((n & (n - 1)) == 0)
+    {
+        return 1; // true
+    }
+    return 0; // false
+}
+
+/**
+ ***EXPLAINATION
+ * how it checks wether an integer can be put
+ * in the form of power of 2 or not is
+ ***any integer number which can be put 
+ *  in the form of power of 2 has only 
+ *  1 bit in the binary reprentation 
+ *  example : n = 16 , 00010000 (8 bits represntation)
+ *  so when we do AND bitwise manipulation with the
+ *  previous number it will always give 0 
+ *  if the integer n can be kept in the form of
+ *  power of 2 ***
+ *  
+ * EXAMPLE :
+ *      n = 16 , 00010000 (8 bits)
+ *      n = n-1 = 15 , 00001111 (8 bits) previous value
+ *      n & (n-1) , 00010000  
+ *                & 00001111
+ *                  00000000
+ *      which is 0 
+ *      so it can be put in the form of power of 2
+ */