w3resource
Python Exercises

Python: Find the second smallest number in a list

Python List: Exercise - 27 with Solution

Write a Python program to find the second smallest number in a list.

Example - 1 :

Python: Find the second smallest number in a list

Example - 2 :

Python: Find the second smallest number in a list

Example - 3 :

Python: Find the second smallest number in a list

Example - 4 :

Python: Find the second smallest number in a list

Sample Solution:-

Python Code:

def second_smallest(numbers):
  if (len(numbers)<2):
    return
  if ((len(numbers)==2)  and (numbers[0] == numbers[1]) ):
    return
  dup_items = set()
  uniq_items = []
  for x in numbers:
    if x not in dup_items:
      uniq_items.append(x)
      dup_items.add(x)
  uniq_items.sort()    
  return  uniq_items[1]   

print(second_smallest([1, 2, -8, -2, 0, -2]))
print(second_smallest([1, 1, 0, 0, 2, -2, -2]))
print(second_smallest([1, 1, 1, 0, 0, 0, 2, -2, -2]))
print(second_smallest([2,2]))
print(second_smallest([2]))

Sample Output:

-2
0
0
None
None

Flowchart:

Flowchart: Find the second smallest number in a list

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Python Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a python program to check whether two lists are circularly identical.
Next: Write a Python program to find the second largest number in a list.

What is the difficulty level of this exercise?