title: Calculating the Difference between 2 numbers in objective-c
body: <p>I know a similar question has been asked before with C#
  <a href="https://stackoverflow.com/questions/339961/difference-between-2-numbers">Difference between 2 numbers</a></p>
  
  <p>But I need to know if objective-c provides some function to find the difference between 2 numbers, (2 NSIntegers, to be specific)</p>
  
  <p>For example the difference between:</p>
  
  <p>100 and 25 is 75</p>
  
  <p>-25 and 100 is 125</p>
  
  <p>100 and -25 is also 125</p>
  
  <p>-100 and -115 is 15</p>
  
  <p>//I know I'm using the same example as the previous </p>
  
  <p>Any help is very much appreciated</p>