Cout << (1<<2) [C++]

Question

so i met this question on the challenge thing, and i dont quite understand how this thing could produce 4. Can someone please explain to me how does this works? thanks in advance.

Answer 1

<< , >> are bitwise lest shift and right shift operators respectively.

x << 2 shifts the bits of numbers towards left by 2
example :
x = 10 ==> (1010) in binary

1010
←
101000 lest shift by 2 position

(101000) in binary = 40 in decimal.
so x<<2 => 40 (if x= 10)
1 position left shift is equivalent to number multiply by 2( until bits doesn't overflow)

x>>2 means shift right by two position.
Example :
x = 10 => 1010
1010
→
10 //shifted right by 2 position
10 in binary => 2 in decimal

so x>>2 = 2 (if x= 10)
1 position right shift is equivalent to number's division by 2.

EDIT:
so 1<<2
1 in decimal = 1 in binary
1
←
100 //left shift by 2
(100) in binary => 4 in decimal
1<<2 => 4

Answer 2

Hello!
It's shift operator, learn more in docs.
https://msdn.microsoft.com/en-us/library/336xbhcz.aspx