title: why performance is zero for the following logic?
body: <p>I wrote this function for codility and got 0 in performance and 100% for correctness. </p>
  
  <pre><code>A = [-1, -3]
  B = [1,2,3]
  C = [1,4,5,6,77,2]
  </code></pre>
  
  <p>The function below is supposed to return smallest integer but not present int list passed to it.</p>
  
  <pre><code>def solution(A):
      temp = 0;
      tempLst = []
      for item in A:
          temp = temp+1
          if temp not in A:
              tempLst.append(temp)
  
      return min(tempLst) if tempLst else max(A) + 1
  </code></pre>
  
  <p>why is it so ? All I wanted is to do it without heap, itertools , partial .</p>