n>>1; n/=2 what is this in c++?

Both of these lines shift the bits over to the right one place

both are equivalent to n = n / 2;

n >> 1 is a bitwise right shift by 1 in C++. a >> b shifts the bit pattern of a the number of bits positions specified by b. Vacated bits on the left are 0-filled if the number is unsigned. If signed, the vacated bits are filled with the sign bit.

Furthermore, the right shift operator only works with a positive right operand. If negative, the result is undefined.

Here's an example of n >> 1. Let's assume that n is 10 (10 in binary is 1010); and we are also going to be using 16 bits here:

    0000000000001010

    0000000000000101

The result is now 0101 which is 5 in binary. a >> b is equivalent to a * 2^b. Note that this only returns the result, it doesn't change the value of n.

n /= 2 is using the compound assignment operator. n is being assigned the result of the division between itself and 2.

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