Python String zfill() Method with Examples

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In the previous article, we have discussed Python String splitlines() Method with Examples
zfill() Method in Python:

The zfill() method appends zeros (0) to the beginning of a string until it reaches the specified length.

If the len parameter value is less than the length of the string, no filling is performed.

Syntax:

string.zfill(len)

Parameters

len: This is Required. A number indicating the string’s desired length.

Return Value:

zfill() returns a copy of the string with 0 to the left filled in. The length of the returned string is determined by the width specified.

  • Assume the string’s initial length is 10. Furthermore, the width is specified as 15. zfill() returns a copy of the string with five ‘0’ digits filled to the left in this case.
  • Assume the string’s initial length is 10. In addition, the width is specified as 8. In this case, zfill() returns a copy of the original string rather than filling ‘0’ digits to the left. In this case, the length of the returned string will be 10.

Examples:

Example1:

Input:

Given string = "hello btechgeeks"
Given number = 10

Output:

hello btechgeeks

Example2:

Input:

Given string = "hello btechgeeks"
Given number = 25

Output:

000000000hello btechgeeks

String zfill() Method with Examples in Python

Method #1: Using Built-in Functions (Static Input)

Approach:

  • Give the first string as static input and store it in a variable.
  • Give the number as static input and store it in another variable.
  • Apply zfill() function to the given first string by passing the above-given number as an argument that Fills the string with zeros until it reaches a length of a given number of characters.
  • Store it in another variable.
  • Print the above result.
  • The Exit of Program.

Below is the implementation:

# Give the first string as static input and store it in a variable.
gvn_fststr = "35"
# Give the number as static input and store it in another variable.
gvn_numb1 = 10
# Apply zfill() function to the given first string by passing the above-given
# number as an argument that Fills the string with zeros until it reaches a
# length of given number of characters.
# Store it in another variable.
rslt = gvn_fststr.zfill(gvn_numb1)
# Print the above result.
print(rslt)

Output:

0000000035

Similarly, do the same for the other strings and print the result.

# Similarly, do the same for the other strings and print the result.
gvn_scndstr = "hello btechgeeks"
gvn_numb2 = 20
print(gvn_scndstr.zfill(gvn_numb2))

Output:

0000hello btechgeeks
gvn_thrdstr = "20.55"
gvn_numb3 = 8
print(gvn_thrdstr.zfill(gvn_numb3))

Output:

00020.55

Method #2: Using Built-in Functions (User Input)

Approach:

  • Give the first string as user input using the input() function and store it in a variable.
  • Give the number as user input using the int(input()) function and store it in another variable.
  • Apply zfill() function to the given first string by passing the above-given number as an argument that Fills the string with zeros until it reaches a length of a given number of characters.
  • Store it in another variable.
  • Print the above result.
  • The Exit of Program.

Below is the implementation:

# Give the first string as user input using the input() function and store it in a variable.
gvn_fststr = input("Enter some Random String = ")
# Give the number as user input using the int(input()) function and store it in another variable.
gvn_numb1 = int(input("Enter some Random number = "))
# Apply zfill() function to the given first string by passing the above-given
# number as an argument that Fills the string with zeros until it reaches a
# length of given number characters.
# Store it in another variable.
rslt = gvn_fststr.zfill(gvn_numb1)
# Print the above result.
print("The result string = ", rslt)

Output:

Enter some Random String = good morning btechgeeks
Enter some Random number = 11
The result string = good morning btechgeeks

Similarly, do the same for other strings and print the result.

Below is the implementation:

# Similarly, do the same for other strings and print the result.
gvn_scndstr = input("Enter some Random String = ")
gvn_numb2 = int(input("Enter some Random number = "))
rslt = gvn_scndstr.zfill(gvn_numb2)
print("The result string = ", rslt)

Output:

Enter some Random String = 250.6
Enter some Random number = 6
The result string = 0250.6

Below is the implementation:

# Similarly, do the same for other strings and print the result.
gvn_thrdstr = input("Enter some Random String = ")
gvn_numb3 = int(input("Enter some Random number = "))
rslt = gvn_thrdstr.zfill(gvn_numb3)
print("The result string = ", rslt)

Output:

Enter some Random String = welcome to btechgeeks
Enter some Random number = 27
The result string = 000000welcome to btechgeeks

Go through our tutorial and learn about various Python String Method Examples and learn how to apply the knowledge while dealing with strings.