What's value of 1<<1? how to calculate it?

2018-06-03 18:01:06

This question already has an answer here:

What are bitwise shift (bit-shift) operators and how do they work? 8 answers

It's just a bit-shift operation.

1 << 0 = 1
1 << 1 = 2
1 << 2 = 4
1 << 3 = 8
etc...

or in binary view

00000001 << 1 = 00000010
00000001 << 2 = 00000100
00000001 << 3 = 00001000

This is left shift operator.

All the bits are shifted one place toward left. Resulting is *2 of the value by shifting value.

1<<3 will be 1*2*2*2=8, shifted 3 bits so three times *2

"<<" indicates left shift (in binary numbers). So 1 << n is the same as 2 to the power of n. However it is most appropriate to look at it in binary,

1<<0 = 1b
1<<1 = 10
1<<2 = 100

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