Python: Convert a string to all uppercase if it contains at least 2 uppercase characters in the first 4 characters

Last update on April 19 2025 13:05:32 (UTC/GMT +8 hours)

Uppercase string if 2+ uppercase chars in first 4.

Write a Python function to convert a given string to all uppercase if it contains at least 2 uppercase characters in the first 4 characters.

Sample Solution:

Python Code:

# Define a function named to_uppercase that takes one argument, 'str1'.
def to_uppercase(str1):
    # Initialize a variable 'num_upper' to count the uppercase letters in the first 4 characters of 'str1'.
    num_upper = 0

    # Iterate through the first 4 characters of 'str1'.
    for letter in str1[:4]:
        # Check if the uppercase version of the letter is the same as the original letter.
        if letter.upper() == letter:
            # If they are the same, increment the 'num_upper' count.
            num_upper += 1

    # Check if the count of uppercase letters is greater than or equal to 2.
    if num_upper >= 2:
        # If there are 2 or more uppercase letters in the first 4 characters, return 'str1' in all uppercase.
        return str1.upper()
    
    # If there are fewer than 2 uppercase letters in the first 4 characters, return 'str1' as it is.
    return str1

# Call the to_uppercase function with different input strings and print the results.
print(to_uppercase('Python'))  # Output: 'Python' (Not all uppercase)
print(to_uppercase('PyThon'))  # Output: 'PYTHON' (All uppercase) 

Sample Output:

Python                                                                                                        
PYTHON

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python function to convert an entire string to uppercase if it contains at least two uppercase characters in its first four characters.
• Write a Python program to check the first four characters for uppercase letters and conditionally convert the string.
• Write a Python program to iterate over the first four characters, count uppercase letters, and then apply str.upper() if condition is met.
• Write a Python program to use a combination of slicing and sum() on boolean expressions to determine if the string should be uppercased.

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