C language function format letter case conversion steps

C Language Function Format Letter Case Conversion Steps

Converting the case of a character in C involves using the toupper() and tolower() functions from the ctype.h header file. These functions take a single character as input and return the uppercase or lowercase equivalent, respectively. To convert an entire string, you need to iterate through each character and apply the appropriate function. The process typically involves these steps:

1. Include the ctype.h header: This header file contains the toupper() and tolower() functions. Without this inclusion, your code won't compile.
2. Iterate through the string: Use a loop (e.g., a for loop) to traverse each character of the input string.
3. Apply toupper() or tolower(): Inside the loop, use either toupper() to convert to uppercase or tolower() to convert to lowercase. The result of this function call should be stored back into the string, replacing the original character.
4. Handle null termination: Remember that C strings are null-terminated. Your loop should stop when it encounters the null character ('

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