code: def find_first_missing_2(a):
      n = len(a)
  
      # eliminate all zeros and all negative numbers
      for i in range(n):
          if a[i] <= 0:
              a[i] = n + 1  # those values won't be used later
  
      # find all numbers in the range and mark all numbers at those positions as negative numbers
      for i in range(n):
          idx = abs(a[i]) - 1
          if idx >= n:
              continue
  
          # mark the element as found
          a[idx] = -abs(a[idx])
  
      # find the first non-negative position
      for i in range(n):
          if a[i] > 0:
              return i + 1
  
      return n + 1
  
label_desc: Use image node_id 2 for calling a global function with example usage: find_first_missing_2(a) and returns: unknown, unknown