C2A1E4_ StrToUpper.c (I used 4 lines of code but you may use any number of lines you wish.) must contain the definition of a function named StrToUpper that returns type size_t and has two parameters, where the first is of type “pointer to char” and the second is of type “pointer to 10 constant char”. StrToUpper must copy the string represented by its second parameter into the memory represented by its first parameter, with any lowercase characters converted to uppercase. The length of the string, not including its null terminator character, is returned Restrictions: 1. Use the toupper standard library function to convert from lowercase to uppercase. 2. You may not call any function other than toupper. 3. You may not use an “if” statement. 4. You may only use one variable other than the two parameter variables and it must be of type “pointer to constant char”. That variable must not be used to count characters.