Simple program problem from upper to lower case

My homework is to create a program that changes an Uppercase letter to a lower case letter. My teacher has not introduced the tolower function, so I am not using it. We were also required to use the cout.put and cin.get functions. Anyway, my program works but when I send it through my teachers automated assignment checker I get 2 warnings (this will cost me points). The warnings are as follows:

Source 1.cpp(39) : warning C4244: 'argument' : conversion from 'int' to 'char', possible loss of data

and

cout.put((int)myLower); // cout.put outputs char found by myUpper + TOLOWER
Source 1.cpp(39): error 734: (Info -- Loss of precision (arg. no. 1) (31 bits to 7 bits))

Here is my code. Thank you for help in advance:

Code:

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#include <iostream>
#include <cstdlib>
using namespace std;


int main()
{
  int myUpper;                                    // declares myUpper an integer allowing us to use const char TOLOWER
  int myLower;
  const int TOLOWER = ' ';                        // initializes TOLOWER to ' ' which has decimal value of 32
 
  cout << "Please Enter an Upper Case Letter: ";  // asks user for myUpper
  myUpper = cin.get();                            // cin.get takes first character entered by user
  myLower = myUpper + TOLOWER;                    // add value of 32 to upper case decimal value to find a lower case
 
  cout << "\nYour Lower Case Letter is: ";
  cout.put((int)myLower);                        // cout.put outputs char found by myUpper + TOLOWER
  cout << "\n\n";                                // newlines entered for clarity

  return(EXIT_SUCCESS);
}

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Are you aware of the char variable type?

Quote:

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Originally Posted by Daved

Are you aware of the char variable type?

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It doesn't matter since cin.get() returns an int and cout.put() takes a char, he will have a warning whichever way he declares the variable.

If you just want to get rid of the warning, you can do a cast:

Code:

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cout.put(static_cast<char>(myLower));

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If you want to avoid casts altogether, you can get input using ">>" instead of the get() function, and then declare all your variables are chars.

>> It doesn't matter since cin.get() returns an int and cout.put() takes a char,
I missed that at first, but according to dinkumware's reference put takes a char and get has a version that works with char as well.

>> you can get input using ">>" instead of the get() function
The assignment requires get and put.

How on earth is anyone supposed to know that adding a space to an uppercase char makes if lowercase?
There are functions for that sort of thing: isupper and tolower, iirc.

Even if you insist on rolling your own, you should do:

Code:

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lower = upper - 'A' + 'a';

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Which it may help to think of as:

Code:

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lower = 'a' + (upper - 'A');

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That is of course after you've determined that it is even an alphabet character and not um say, a digit or punctuation mark etc.