Common bit operations

bits.cpp

// Get the ith bit of num.
bool getBit(int num, int i) {
   return (num & (1 << i)) != 0;
}
           
// Set the ith bit of num.
int setBit(int num, int i) {
    return num | (1 << i);
}
           
// Clear the ith bit of num.
int clearBit(int num, int i) {
    int mask = ~(1 << i);
    return num & mask;
}
           
// Clear from the highest to the ith bit of num.
int clearBitsMSBthroughI(int num, int i) {
    int mask = 1 << i - 1;
    return num & maskl
}
           
// Clear from the ith to the lowest bit of num.
int clearBitsIthrough0(int num, int i) {
    int mask = ~(1 << (i+1) - 1);
    return mask & num;
}