[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