BitManipulation.java

/**
 * Fundamental bit manipulation operations you must know Time Complexity: O(1)
 *
 * @author Micah Stairs
 */

public class BitManipulation {

 // Sets the i'th bit to 1
 public static int setBit(int set, int i) {
 return set | (1 << i);
 }

 // Checks if the i'th is set
 public static boolean isSet(int set, int i) {
 return (set & (1 << i)) != 0;
 }

 // Sets the i'th bit to zero
 public static int clearBit(int set, int i) {
 return set & ~(1 << i);
 }

 // Toggles the i'th bit from 0 -> 1 or 1 -> 0
 public static int toggleBit(int set, int i) {
 return set ^ (1 << i);
 }

 // Returns a number with the first n bits set to 1
 public static int setAll(int n) {
 return (1 << n) - 1;
 }

 // Verifies if a number n is a power of two
 public static boolean isPowerOfTwo(int n) {
 return n > 0 && (n & (n - 1)) == 0;
 }
}