[Exercise 03] Caesar Cipher Decoder

Question

You have received an encrypted message from Julius Caesar-- the message is ebiil.  You are asked to decipher the message in order to understand what Caesar trying to say to you.

Hint

Luckily, Caesar has given you a hint, he says: 'I, myself, encoded the message by shifting every word backwards by 3.' 

Solution

Write a program that receives 5 characters 'ebiil'. Then decode those characters into 5 new characters.

Example

#include <stdio.h>

int main(int argc, char *argv[]) {


	char a;
    	char b;
	 	
	scanf("%c%c", &a, &b);
	
	//decode the message how??
	
	printf("%c%c", a,b);
	
	return 0;
}

Input

ebiil

 

 

 

 

 

 

 

 

 

 

Output

hello

** REMEMBER ** 
This is an online-compiler, don't put anything except the codes. If you want to make a comment, please use // or /* */

Answer 1

Hidden content!
 * **       ** *   
#include  *  * * *     * 
int main(int argc, char *argv[]) {
   *   *  *  *** **  *    **   lettera;
   *** * **   ****  ***** * letterz;
   **** ** *** *  *** *   **  letterx;
 * * *   **** * *** **** ** *     letterc;
*   *  ***     ** *    letterv;
      ***** * **
 **** ***   *  ****   *  ** * *   input the letter to encode: ");
 *  *  * *****      *  *  *  *   **** ***  *   * ***  **    ***** ** *** *  **    *******  ***** **   *** *  *  ***    
 **** ** *  **  **  *  *   *  = lettera + 3;
**   ** ******    **   *   * * = letterz + 3;
 *  ** ***  ** * * * ** *** *  = letterx + 3;
***  *    *      ***   ** * *   * *   = letterc + 3;
   *** * ***    *      * *** ****** = letterv + 3;
  ** *     * *    **    
 *    ** *** ** **** * *     *      *** ** *** ***   *** *******   **   ** *  * **    
  * ****** *** ** ***
*** * **** ** * **** ***  * * 0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Nice, it is correct. You might be wondering why your automatically-generated score is 0.
That's because it expects its output to be only 'hello'. However, what your program showed was:
     Please input the letter to encode: ebiil
     hello

Anyway, great job. Full marks.

Answer 2

Hidden content!
** **   ** ** *   *  
 *  ***  ***   * * * 

int  ***    argc, char  *** {
 * * *   ** ** * char  ***   
 ** *   * ** *** * 
*  *  **  * * * a = **  *
      * *  * b = ****** 
 * ** * *    * c =   *     
      **  **** d = **     
* * ****  ** * ** e =  * * *  **
***** *   *    * 
*  * **  *** ** a += 3;
 ** * ****   * b += 3;
***   *       c += 3;
 ******   ** ** d += 3;
**** ***  *  ** ** e += 3;

****  * * ****   **
 * ******    ****  ** ** 
**  * ** *  *     * 
****  **** ***  ** *  **
  * ****   ****  ***  *
*** * *    **** *  
** *    ** **   
 *       *   
   ** *    *   *  * *****  *  **  0;
}

Comments

Case 0: Correct output