Python: Find the set of distinct characters in a string, ignoring case

Last update on April 17 2025 13:09:23 (UTC/GMT +8 hours)

Distinct Characters in String

Write a Python program to find the set of distinct characters in a given string, ignoring case.

Input: HELLO
Output:
['h', 'o', 'l', 'e']

Input: HelLo
Output:
['h', 'o', 'l', 'e']

Input: Ignoring case
Output:
['s', 'n', 'c', 'o', 'e', 'i', 'r', 'g', 'a', ' ']

Visual Presentation:

Python: Find the set of distinct characters in a string, ignoring case.

Sample Solution-1:

Python Code:

# License: https://bit.ly/3oLErEI

# Define a function named 'test' that takes a string 'strs' as input
def test(strs):
    # Convert the input string to lowercase, create a set of distinct characters, and return it as a list
    return [*set(strs.lower())]

# Assign a specific string 'strs' to the variable
strs = "HELLO"
# Print a message indicating the original string
print("Original string:", strs)
# Print a message indicating the operation to be performed
print("Set of distinct characters in the said string, ignoring case:")
# Print the result of the test function applied to 'strs'
print(test(strs))

# Assign another specific string 'strs' to the variable
strs = "HelLo"
# Print a message indicating the original string
print("\nOriginal string:", strs)
# Print a message indicating the operation to be performed
print("Set of distinct characters in the said string, ignoring case:")
# Print the result of the test function applied to 'strs'
print(test(strs))

# Assign another specific string 'strs' to the variable
strs = "Ignoring case"
# Print a message indicating the original string
print("\nOriginal string:", strs)
# Print a message indicating the operation to be performed
print("Set of distinct characters in the said string, ignoring case:")
# Print the result of the test function applied to 'strs'
print(test(strs))

Sample Output:

Original string: HELLO
Set of distinct characters in the said string, ignoring case:
['o', 'e', 'l', 'h']

Original string: HelLo
Set of distinct characters in the said string, ignoring case:
['o', 'e', 'l', 'h']

Original string: Ignoring case
Set of distinct characters in the said string, ignoring case:
['o', ' ', 'i', 'r', 'e', 'g', 'a', 'n', 'c', 's']

Flowchart:

Sample Solution-2:

Python Code:

# License: https://bit.ly/3oLErEI

# Define a function named 'test' that takes a string 'strs' as input
def test(strs):
    # Convert the input string to lowercase, create a set of distinct characters, and convert it back to a list
    return list(set(strs.lower()))

# Assign a specific string 'strs' to the variable
strs = "HELLO"
# Print a message indicating the original string
print("Original string:", strs)
# Print a message indicating the operation to be performed
print("Set of distinct characters in the said string, ignoring case:")
# Print the result of the test function applied to 'strs'
print(test(strs))

# Assign another specific string 'strs' to the variable
strs = "HelLo"
# Print a message indicating the original string
print("\nOriginal string:", strs)
# Print a message indicating the operation to be performed
print("Set of distinct characters in the said string, ignoring case:")
# Print the result of the test function applied to 'strs'
print(test(strs))

# Assign another specific string 'strs' to the variable
strs = "Ignoring case"
# Print a message indicating the original string
print("\nOriginal string:", strs)
# Print a message indicating the operation to be performed
print("Set of distinct characters in the said string, ignoring case:")
# Print the result of the test function applied to 'strs'
print(test(strs))

Sample Output:

Original string: HELLO
Set of distinct characters in the said string, ignoring case:
['h', 'o', 'l', 'e']

Original string: HelLo
Set of distinct characters in the said string, ignoring case:
['h', 'o', 'l', 'e']

Original string: Ignoring case
Set of distinct characters in the said string, ignoring case:
['s', 'n', 'c', 'o', 'e', 'i', 'r', 'g', 'a', ' ']

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to extract the set of distinct characters from a string, ignoring case differences.
Write a Python program to convert a string to lowercase and return a list of unique characters found within it.
Write a Python program to use set operations to filter out duplicate characters from an input string.
Write a Python program to iterate over a string and build a set of characters, then output the sorted result.

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Python Code Editor :

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