Generally, computers store numbers with decimal places as floating point numbers, which aren't stored exactly. The Some solutions are

• work with some multiple of the numbers (eg 100 for yours), so you could use $x = 10000; $y = -10001; print $x - $y;
• use printf to round your answer, like so printf "%0.2f", $x+$y

  ---

  In reply to Re: can't Understand output by FunkyMonk
  in thread can't Understand output by Anonymous Monk

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