Simple program problem from upper to lower case

steals10304 · 08-11-2009, 03:39 PM

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:

#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);
}

Daved · 08-11-2009, 03:53 PM

Are you aware of the char variable type?

bithub · 08-11-2009, 03:57 PM

Quote:

Originally Posted by Daved

Are you aware of the char variable type?

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:

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

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.

Daved · 08-11-2009, 04:11 PM

>> 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.

iMalc · 08-12-2009, 02:31 AM

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:

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

Which it may help to think of as:

Code:

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

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.

08-11-2009, 03:39 PM	#1
steals10304 Registered User Join Date: Aug 2009 Posts: 30	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: #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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08-11-2009, 03:53 PM	#2
Daved Registered User Join Date: Jan 2005 Posts: 7,137	Are you aware of the char variable type?
Daved is offline

08-11-2009, 04:11 PM	#4
Daved Registered User Join Date: Jan 2005 Posts: 7,137	>> 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.
Daved is offline

08-12-2009, 02:31 AM	#5
iMalc Algorithm Dissector Join Date: Dec 2005 Location: New Zealand Posts: 2,476	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: lower = upper - 'A' + 'a'; Which it may help to think of as: Code: lower = 'a' + (upper - 'A'); 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. __________________ My homepage Advice: Take only as directed - If symptoms persist, please see your debugger
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