// Our course implementation of the toupper function
#include<iostream>
using namespace std;
// Precondition: char variable containing upper or
// lower case letter is passed in
// Postcondition: letter in variable has been
// capitalized
void toupper(char &letter);
int main()
{
char input;
// Get letter from user
cout << "Give me a letter: ";
cin >> input;
// Capitalize letter and report result
toupper(input);
cout << "Letter in upper case is "
<< input << endl;
return 0;
}
void toupper(char &letter)
{
if(letter>90)
letter-=32;
}