[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