title: Find index value of where a appears as substring in b | Swift
body: <p>I am trying to write a function when passed two integers the function returns the left most position when a appears in b, this is about the decimal representation of where a appears in b counting from 0, so 66 appears at position 4 in 22331166.</p>
  
  <p>So I convert both integers two strings, then check in b constains a, however how can I then find the left most position a appears in b ? </p>
  
  <pre><code>public func solution(_ A : Int, _ B : Int) -&gt; Int {
  
  let a = String(A)
  let b = String(B)
  
  
  if b.contains(a) {
  
  
  } else {
      return 0
  }
  
  return 1
  }
  
  solution(33, 88553344)
  </code></pre>
  
  <p>The function should return 3, as 88 should be 1, 55 is 2 and 33 is 3. </p>