Character Arrays

I've got write a program that reads a data file which contains a paragraph. I need to take each letter and convert it to two letters higher. So a-->c d-->f and y-->{. The spaces must not be changed. It needs to print the output into another data file. I must use arrays and have it in int main().

I would appreciate it if someone could point me in the write direction or show me a program that is somewhat like what I need.
Thanks

What, in the above problem, do you not know how to do?

I know how to open the file and I know how to output a data file but I'm not sure how to read from the file. I know I need to use get() I think but I'm not sure how to get char array set up to read the paragraph.

Quote:

---

Originally Posted by JHaney

I know how to open the file and I know how to output a data file but I'm not sure how to read from the file. I know I need to use get() I think but I'm not sure how to get char array set up to read the paragraph.

---

Don't use a char array to read the file. Instead, read the data into a char variable. Then, use a char array to store the converted characters. A char array works just like a numerical array, and it can be used to hold values just like a numerical array can--the only difference is that the values the char array holds are char's rather than numbers. Here is an example:

Code:

---

#include <iostream>
using namespace std;

int main()
{

        char input = 'a';
        char converted[100] = {0};

        converted[0] = input;

        input = 'b';
        converted[1] = input;

        input = 'c';
        converted[2] = input;
       
        cout<<converted<<endl;
       
        return 0;
}

---

well I don't know how to read a file from c++, but you can save the caracters in an int array, so when you read a character just put something like:

intArray[i] = input + 2;

assuming that input is a char and have the value of the character read from the file...

Thanks for the replies. Now I'm wondering how to get one letter at a time from the data file and how to store it. I can use the stuff yall have posted so thanks for that.

Code:

---

char ch;
while( inputFile.get(ch) )
{
    //do something with ch
}

---

When reading from a file, you should use the read statement as your while conditional. That way if there is an error while reading from the file, things will terminate correctly. Otherwise, you could get stuck in an infinite loop. That version of get() will return an object that will evaluate to false if there is an error while reading from the file.

You should be aware that at the end of a line in a file, there is an invisible '\n' character, which was placed there when you hit return to start a new line. get() will read in the '\n' character, so not only do you have to leave spaces alone, you also have to check for a '\n'.