Programming Forums > Projects > Existing Project Development

Jessehk · May 27th, 2005, 4:30 PM

I don't know if any of you have read Digital fortress by Dan Brown, but he describes an ancient method of encrypting messages by using a square.

4 letters: test

they would be displayed like this:

T E
S T

and the encrypted message would be this: TSET.

I wanted to create a tool that would encrypt and decrypt these messages for me.

This is what I have so far, and it works. The decrypter will come later, this is simply the basis for the program.

note:the code only works if you enter in 4 letters or less. It will be updated however to accept up to 100 characters.

I'm sorry, I don't like comments. I'm too lazy :p ( I know, I know...bad habit).

Any questions or suggestions would be welcome.

(Toggle Plain Text)

#include <stdio.h>
#include <ctype.h>
#include <string.h>

int main()
{
	int length, x, difference;
	char input[144];
	
	
	printf("Enter a phrase to be encrypted:");
	putchar('\n');
	gets(input);
	length = strlen(input);
	if(length <=4)
	{
		if(length > 0 && length < 4)
		{
			difference = 4 - length;
			for(x=0;x<difference;x++)
			{
				strcat(input,"*");
			}
			length = strlen(input);
		}
		for(x=0;x<length;x++)
		{
			if(!isalnum(input[x]))
			{
				input[x] = '*';
			}	
		}
		printf("\nHere is you encrypted text: %c%c%c%c", input[0],input[2],input[1],input[3]);
	}
	return(0);
}

May 27th, 2005, 4:30 PM	#1
Jessehk The Oblivious One Join Date: May 2005 Location: Ontario, Canada Posts: 639 Rep Power: 4	"grid" encryptor I don't know if any of you have read Digital fortress by Dan Brown, but he describes an ancient method of encrypting messages by using a square. 4 letters: test they would be displayed like this: T E S T and the encrypted message would be this: TSET. I wanted to create a tool that would encrypt and decrypt these messages for me. This is what I have so far, and it works. The decrypter will come later, this is simply the basis for the program. note:the code only works if you enter in 4 letters or less. It will be updated however to accept up to 100 characters. I'm sorry, I don't like comments. I'm too lazy :p ( I know, I know...bad habit). Any questions or suggestions would be welcome. (Toggle Plain Text) #include <stdio.h> #include <ctype.h> #include <string.h> int main() { int length, x, difference; char input[144]; printf("Enter a phrase to be encrypted:"); putchar('\n'); gets(input); length = strlen(input); if(length <=4) { if(length > 0 && length < 4) { difference = 4 - length; for(x=0;x<difference;x++) { strcat(input,""); } length = strlen(input); } for(x=0;x<length;x++) { if(!isalnum(input[x])) { input[x] = ''; } } printf("\nHere is you encrypted text: %c%c%c%c", input[0],input[2],input[1],input[3]); } return(0); } #include <stdio.h> #include <ctype.h> #include <string.h> int main() { int length, x, difference; char input[144]; printf("Enter a phrase to be encrypted:"); putchar('\n'); gets(input); length = strlen(input); if(length <=4) { if(length > 0 && length < 4) { difference = 4 - length; for(x=0;x<difference;x++) { strcat(input,""); } length = strlen(input); } for(x=0;x<length;x++) { if(!isalnum(input[x])) { input[x] = ''; } } printf("\nHere is you encrypted text: %c%c%c%c", input[0],input[2],input[1],input[3]); } return(0); } Last edited by Jessehk; May 27th, 2005 at 4:36 PM.

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Switch to Hybrid Mode Threaded Mode

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Programming Forums > Projects > Existing Project Development

"grid" encryptor