Bit Manipulation

1
public boolean isPowerOfTwo(int num) {
2
    return (num & (num - 1)) == 0;
3
}

1
public int clearKthBit(int num, int k) {
2
    return num & ~(1 << k);
3
}

1
public int countSetBits(int num) {
2
    int count = 0;
3

4
    while (num > 0) {
5
        count += num & 1;
6
        num >>= 1;
7
    }
8

9
    return count;
10
}

1
public int divideByPowerOfTwo(int num, int k) {
2
    return num >> k;
3
}

1
public int getRightmostSetBit(int num) {
2
    return num & -num;
3
}

1
public int multiplyByPowerOfTwo(int num, int k) {
2
    return num << k;
3
}

1
public int setKthBit(int num, int k) {
2
    return num | (1 << k);
3
}

1
public int[] swapVariables(int num1, int num2) {
2
    num1 ^= num2;
3
    num2 ^= num1;
4
    num1 ^= num2;
5
    return new int[] { num1, num2 };
6
}

1
public boolean testKthBit(int num, int k) {
2
    return (num & (1 << k)) != 0;
3
}

1
public int toggleKthBit(int num, int k) {
2
    return num ^ (1 << k);
3
}