MapleStory Calculator [Version 1.00b]

Here's the problem:

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As you can see, my range is 500~1000, I'm lvl 50 and the monster is lvl 100, it has 200 wdef.

My range should be 500(1-(100-50)/(200-100))-200*.6 = 130, but your program does it as
500-200*.6 = 380

Max should be 1000(1-(100-50)/(200-100))-200*.5 = 400, but it reads it as 1000-200*.5 = 900

Its not taking the level multipler into effect. Now if I reduce my level to 1 and the monster's to 101 I get 1 damage

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Most of the time the minimum displays as 2^31

And if you did the 2^31 just for fun, maple uses 2^31-1 due to a 0 placeholder.