[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