Python Pad Number | Programming Tutorials

Introduction

In Python, sometimes we need to pad a number with leading zeros to make it a certain length. For example, we might want to pad the number 7 to be 000007. In this challenge, you will need to write a function that pads a given number to the specified length.

Skills Graph

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Pad Number

Write a function pad_number(n, l) that takes in a number n and a length l and returns a string that represents the padded number. The function should pad the number with leading zeros to make it l digits long. If the number is already l digits long, the function should return the number as a string.

To pad the number, you can use the str.zfill() method. This method takes in a length and pads the string with leading zeros until it is that length. For example, "7".zfill(6) would return "000007".

def pad_number(n, l):
  return str(n).zfill(l)

pad_number(1234, 6); ## '001234'

Summary

In this challenge, you wrote a function that pads a given number to the specified length. You learned how to use the str.zfill() method to pad a string with leading zeros.