Parameters of toupper() in C++
It accepts a single parameter:
ch: It is the character to be converted to uppercase.
toupper() in C++
In C++, the toupper() function converts a lowercase alphabet to an uppercase alphabet. It is a library function defined inside the ctype.h header file. If the character passed is a lowercase alphabet, then the toupper() function converts it to an uppercase alphabet. This function does not affect an uppercase character, special symbol, digits, or other ASCII characters.