Python - Given a list of integers that represents a decimal value, increment the last element by 1

When it is required to increment the last element by 1 when a decimal value is given an input, a method named ‘increment_num’ is defined that checks to see if the last element in the list is less than 9. Depending on this, operations are performed on the elements of the list.

Example

Below is a demonstration of the same

def increment_num(my_list, n):

   i = n

   if(my_list[i] < 9):

      my_list[i] = my_list[i] + 1
      return

   my_list[i] = 0
   i -= 1

   increment_num(my_list, i)

n = 4

my_list = [0, 1, 4, 7, 9]
print("The list is :")
print(my_list)
increment_num(my_list, n)

if(my_list[0] > 0):
   print(my_list[0], ", ")
print("After incrementing, the list is :")
print(my_list)

Output

The list is :
[0, 1, 4, 7, 9]
After incrementing, the list is :
[0, 1, 4, 8, 0]

Explanation

• A method named ‘increment_num’ is defined that takes the list, and a number as parameters.

• The last element in the list is checked to be less than 9.

• If yes, the last element is incremented by 1, and is returned as output.

• Otherwise, if the last element is 0, the index is decremented by 1, and the ‘increment_num’ method is called again.

• Outside the function, the value of ‘n’, and the list are defined.

• They are displayed on the console.

• The method is called by passing the required parameters.

• The output is displayed on the console.