Question

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Absolute Beginner's Guide to Bit Shifting?

anyone can explain me that operator << or >>

Answer 1

The << and >> operators are bitshift operators. x << 1 shifts all the bits in x up to the next most significant bit, effectively multiplying by 2. More generally, x << n shifts the bits up n positions. To understand how this operation works it is easiest to look at the binary representation:

3         0000011 =  3
3 << 1    0000110 =  6
3 << 2    0001100 = 12
3 << 3    0011000 = 24

Similarly the >> operator shifts the bits down:

58        0111010 = 58
58 >> 1   0011101 = 29
58 >> 2   0001110 = 14
58 >> 3   0000111 = 7
58 >> 4   0000011 = 3
58 >> 5   0000001 = 1
58 >> 6   0000000 = 0