I have invented a trick to reverse a number

so lets know how to do it, lets take a number 32

step 1. take the largest number and lowest number (largest number = 3 and lowest number = 2)

step 2.find the difference of the largest and smallest number (3 - 2 = 1)

step 3.in largest number subtract the difference and in the lowest number add the difference (3 - 1 = 2, 2 + 1 = 3)

step 4.write the first number and the second number from the step 3 calculation (first number = 2 and second number = 3)