[Tutor] << operator ?

[Kalle Svensson]

[Prahlad Vaidyanathan]
> What does this "<<" operator do ? IIRC, it is a bit-wise shift operator,
> but I don't know what that means either :-(

Consider a number, say 4711.  It is represented in the computer as the
binary number 00000000 00000000 00010010 01100111.

When shifted one step to the left (<< 1), this becomes
00000000 00000000 00100100 11001110, or 9422.  This is, as you can
see, twice the original number.

4711 << 8 is 00000000 00010010 01100111 00000000, 1206016, 256 * 4711.

The >> operator works in the same way, but a different direction:
4711 >> 8 is 00000000 00000000 00000000 00010010, 18, 4711 / 256.

Any clearer?

Med utmärkt högaktning,
  Kalle
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