What is the “<<” operator in C++? [closed]

Answer 1

It's the left shift operator. It shifts the value left by 2 bits, effectively multiplying it with 2 to the power of 2 (the shift amount).

a << b

Is the same as:

a * (2 to the power of b)

Answer 2

it is a bitshift operator in c++.

Answer 3

It's a bitwise shift left operator that means you assign h the value when shifted left by two bits effectively multiplying h by 2 to the power of 2:

h << 2 == h * (2 ^ 2)

You can find more information about it here.

Hint: Next time search http://www.google.com first.

Answer 4

It is a bit shift operator (in this context on a long variable).

It shifts all bits over by 2 places, resulting in a multiplication by four (just as you would add two digits in a base 10 number to multiply by 100. To generalize, shifting n places will multiply the number by 2^n). For example:

unsigned int x = 0xA;     // x = 1010  (10 base 10)
unsigned int y = x << 1;  // y = 10100 (20 base 10)

You can perform division by two by shifting the bits to the right (i.e., chopping one off the end)

unsigned int x = 0xA;     // x = 1010  (10 base 10)
unsigned int y = x >> 1;  // y =  101  (5 base 10)