• Kazumara@discuss.tchncs.de
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      2 days ago

      Leap years are each fourth year, except each hundredth year, except each thousandth fourhundredth year.

      1896 leap year
      1900 not leap year
      1904 leap year

      1996 leap year
      2000 leap year
      2004 leap year

      2096 leap year
      2100 not leap year
      2104 leap year

      Then you just arrange the 10 year window in different positions to overlap 1 to 3 leap years to reveal the three outcomes of the bug.

      - / - - - / - - - /
      - - / - - - / - - -
      - - 0 - - - / - - -

      - is a normal year, / is a leap year, 0 is an exceptional non-leap year.