The output of the following code is '8'. How?

Question

int x=2;
Console.WriteLine(x<<2);

Answer 1

It is moved 2 bits to the left, bitwise.
Consider 2 as binary:

0010

If you move the bits by 2 spaces to the left (what this operation does), you get:

1000

Which in decimal is 8 :)

Answer 2

In this context, << is a binary operation, also known as a "shift". The shift direction is "left", 2 times.

First, represent the base-10 number 2 in binary (base 2). This one has two leading zeros because it makes my examples line up:
0010
= 0*2³ + 0*2² + 1*2¹ + 0*2°
= 0 + 0 + 2 + 0
= 2

Now shift the entire thing left two spots, filling in zeros at the right (and dropping the extra leading zeroes for simplicity):
1000
= 1*2³ + 0*2² + 0*2¹ + 0*2°
= 8 + 0 + 0 + 0
= 8

Another way to look at shifting is that each left shift multiplies the value by 2:

0011 = 3 ( 2+1 )
0110 = 6 ( 4+2 )
1100 = 12 (8+4 )

Two shifts is double, then double again.

Answer 3

Left bit shift is pretty simple to understand once you know a little binary. The shift amount is equal to taking the number and multiplying it by 2 the amount of shift that is taking place. In other words with: 5 << 4 the result will be equal to 5 * 2 * 2 *2 * 2

in C#:

Console.WriteLine(42<<5);

is equivalent to:

int num = 42;
int shift = 5;

for(int i = 0; i < shift; ++i) {
num*=2;
}

Answer 4

2 in bits is 0010

we shift this number to the left by 2 bits, so we get 1000 (in bits)
When we covert it to decimal you get 8 ^^

Answer 5

Thanks bro...