java - reverse formula conversion -

I have a formula that calculates the status for Y, here it is:

  double y = ...; Double minx = ..; Double Scale Y = ..; Int MAX_COORD = (1 & lt; & lt; 16) - 1; Int.s = ~ (int) ((y - minY) / scaleY * MAX_COORD) & amp; 0xFFFF;  

And now I have the C, and I need to calculate y:

  y = (sy * scaleY) / MAX_COORD + minY ;  

But the conversion is not equal .. I think because I do not know how ~ and amp; Operator

~ x is -x-1, it is itself inversion.

X & amp; 0xffff is equal to x% 65536. Since many values ​​can map to the same result, you can not reverse it, but if the result is in the proper range, then you can consider it as identifying it, that is, leave it.