Encrption 1

[Scooby316]

Hi all

I am having some bother with a while loop that is driving me nuts. The code works but doesn't seem to encrpt the inputted text. It works on that it will encrpt until a higher letter is entered that small a to z.

c = (unsigned char)getchar(); /* read in first character */

/*
* main encryption/decryption loop
* loop while characters are lower case letters or spaces
*/
while (c>='a' && c<='z' || c==' ')
{
if (c==' ')
{
switch (type)
{
case 'd':
c = decrypt;
default:
c = encrypt;
}
}
putchar(c); /* display encrypted/decrypted character */
c = (unsigned char)getchar(); /* get next character */
}
/*
* end of main while loop
*/

 

[Salem]

What are encrypt and decrypt in your code?
If they're meant to be functions, they're not being called.

Also, your code only actually tries to encrypt/decrypt space characters. Everything else is unaffected.

--

 

[Scooby316]

Hi Salem

the other code to de/ encrypt is

/*
* function encrypt()
* ==================
* encrypts a single character
*/
unsigned char encrypt(unsigned char letter)
{
unsigned char r;
r = (unsigned char)random(26);
letter = letter + r;
if (letter>'z')
{
letter = letter - 26;
}
return(letter);
}
/*
* end of encrypt()
*/


/*
* function decrypt()
* ==================
* decrypts a single character
*/
unsigned char decrypt(unsigned char letter)
{
{
unsigned char r;
r = (unsigned char)random(26);
letter = letter - r;
if (letter>'z')
{
letter = letter + 26;
}
return(letter);
}
/*
* end of decrypt()
*/

 

[Salem]

> c = encrypt;
This doesn't call the function

Use this
c = encrypt(c);

--

 

[Scooby316]

Hi Salem

Cheers got the encryption working? I don't think the decrpytion process is working know. After encryption the word when put into the decryption comes back with a differnet word. The fun of it all.

 

[Scooby316]

Cheers Salem

well sorted now!

Me very happy and can now sleep!

 

[Salem]

Well your decrypt() isn't the inverse of your encrypt() for starters.

And you need to make sure you reset the seed value for your random number generator.



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