Bitwise opetations assume an infinite number of 1s on the left for negative numbers (2s compliment) e.g., ~-1 == 0 (-1 is an infinite number of 1s that are converted to 0 by ~ (invert) operator ).

  3 == 011
  2 == 010
  1 == 001
  0 == 000
  -1 == ..111
  -2 == ..110
  -3 == ..101