Hey all, I've been making a caesar cipher but seem to have encountered a problem. My program reads an integer from a text file and stores it as the shift value. Then my goal was to add that shift value to the alphabet array. Here is a part of my code:

inFile.get (shift); 

    cout << "Original Alphabet: ";
    for(int i = 0; i < length; i++)
        cout << alphabet[i];
    cout << endl;

    cout << "Shift Value: " << shift << endl;

    cout << "Encrypted Alphabet: ";
    for(int i = 0; i < length; i++)
    {
        Caesar[i] = alphabet[(i + shift) % length];
        cout << Caesar[i];

My issue is that the shift value comes out as 4, however the caesar array comes out identical to the alphabet array.

I just used your code, and with shift of 4, the Caesar array is:
efghijklmnopqrstuvwxyzabcd

Just what it should be. What are you seeing as a problem?

There's no obvious error in the snippet of code you've posted.
A complete working example based on your code:

#include <iostream>

int main()
{
    using std::cout;
    using std::endl;

    const size_t length = 26;

    const char alphabet[length] = {
        'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
        'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'
    };

    char Caesar[length] = {0};

    int shift = 4;

    cout << "Original Alphabet:  ";
    for(int i = 0; i < length; i++)
        cout << alphabet[i];
    cout << endl;

    cout << "Shift Value: " << shift << endl;

    cout << "Encrypted Alphabet: ";
    for(int i = 0; i < length; i++)
    {
        Caesar[i] = alphabet[(i + shift) % length];
        cout << Caesar[i];
    }

    std::cin.get();

    return 0;
}

/* 
Original Alphabet:  ABCDEFGHIJKLMNOPQRSTUVWXYZ
Shift Value: 4
Encrypted Alphabet: EFGHIJKLMNOPQRSTUVWXYZABCD
*/

I know that works fine, but that is not my full code. When I read from a file and try to execute the shift some of the letters are shifted incorrectly

You need to post the relevant code so that we can see where the actual problem is, not a snippet that works fine.

inFile.get (shift);
Is it that you are getting in the shift value as a character, but you are using as the number it represents?

Actually, that input gets a string. Do you convert it to integer somewhere you're not showing?

No I didn't convert it to an integer as I didn't know how. The inFile.get (int) doesn't work and when i made shift a char, it managed to work. I am able to get a semi functional program, however there are a few characters that are off.

Is there a reason you don's use:

int shift;
infile >> shift;

That would store the value as an integer.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.