Parse String and Display it Alphabetically

[laurie1388]

I'm in an Intro to Software Development course at FIT and I have a homework assignment that I have no idea what to do about. Can anyone help? Do I need to use ASCII? If so, how?

Here's the assignment:

Write a program to accept a string as input from the user.
The program should verify that the input string contains nothing but alphabets.
If the string is not valid, the program should ask the user to input it again.
The program should automatically sort the characters in the string in ascending order (A-Za-z), and display it.


Thanks in advance!

-Lauren

[sicarie]

Okay, so breaking down your requirements you need a few things:

1) a string input by the user

2) parsing functionality to break the string into individual characters

3) arrangement of the characters into alphabetical order

4) displaying the characters

Does that sound like a complete list to you? If so, how many of those do you know how to do? Which seem like the easiest?

[laurie1388]

This is what I've got so far (minus the stuff that goes at the end to end the program):


[CODE=cpp]#include <iostream>
#include <string>
using namespace std;
int main ()

{

string s;

cout <<"Please enter some text.";
cin >>s;[/CODE]

[Ganon11]

OK, so you've got the string. Now how are you going to make sure all the characters are alphabetical characters? If there is a non-alphabetic character, how will you keep asking the user for input until it is correct?

As for sorting, check the Howtos section for some very simple sorting methods.

[laurie1388]

That's pretty much my problem. I know how to do an if statement and a do while loop to ask for a different input, but I don't know how to get it to distinguish between letters and numbers or how to define them. Someone told me to use ASCII. I know what that is and which numbers equal the letters I need, but I don't know how to incorporate that into my code at all.

[Ganon11]

Check out the isalpha(char) function.