10-19 Exercise 3: Prints the number with its digits reversed

Question

Write a program that input four-digit number, then prints the number with its digits reversed .

寫一個輸入4位數字，反轉輸出這個數字的值

Example input: 

5455

Example output:

5545

Example input: 

5400

Example output:

45

Answer 1

Hidden content!
#include <stdlib.h>

using namespace std;

int main()
{
   ** *  *    * ***   **    *   x;
**   **** *** **   * *  ** * **** *****
 * ****   **  ** * ** ** ** ** **  * *  **** **** * *** *  * ** * * * ** *** *               
   *  ** * *  **  *******   **  *  * ***    * ***       * ****  *   **  ***   
 *   **  *  *** *  *  **  *  **** * * **  ** * * *       *    ** *** * *** **** *   *********     **       
 **  *  ***** * ** **   ***   *  ****   **  *    **
*  **   **** ** ** *** * *** **  ** *****  **** *      ** **  * ***********   * * *    ;
*****  ***    *** *****   
**    ****    *      ***   *   0;
}

Comments

prog.c:3:1: error: unknown type name 'using'
 using namespace std;
 ^~~~~
prog.c:3:17: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'std'
 using namespace std;
                 ^~~
prog.c: In function 'main':
prog.c:7:5: error: unknown type name 'string'
     string x;
     ^~~~~~
prog.c:8:11: error: 'cin' undeclared (first use in this function)
     while(cin>>x){
           ^~~
prog.c:8:11: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:24: error: request for member 'length' in something not a structure or union
         for(int i=0;i<x.length();i++){
                        ^
prog.c:11:22: error: request for member 'length' in something not a structure or union
             re[i]=x[x.length()-i-1];
                      ^
prog.c:13:9: error: 'cout' undeclared (first use in this function)
         cout<<atoi(re)<<endl ;
         ^~~~
prog.c:13:25: error: 'endl' undeclared (first use in this function)
         cout<<atoi(re)<<endl ;
                         ^~~~

Answer 2

Hidden content!
#include <iostream>
#include *   *   * *** * * 

using namespace std;

int main()
{
* ***     *  ** *     ** ***  x;
* *  *   ******* *** *** ***  *    * *  **** ** 
*   *** ********* *  **   * **         ***** *** *  *  **  *  *  *     * * * ***             
**  *  *    ***   * ******  **** **   * *  **** * ***    * * *** **   * **** *  
  *  ***   **** * **   **** * * ** *** *     * * * * ** * ******  * ******* **  ***    ** *  *** * **        
 ** *  **  *     **   *       *     ** *** * *  *****  **
* * * ****  ***    ** *   **    ***  *     * ** *  *   *  * **  **      *   **** *    *** ;
* ** *  *  * *** *****  *   *** *
 **    *   * *     ** * *  0;
}

Comments

prog.c:1:20: fatal error: iostream: No such file or directory
 #include <iostream>
                    ^
compilation terminated.

Answer 3

Hidden content!
  *          ** * 
**    **
{
 *  ** *  ** *    ****  
 ****    * * *   ** *  **
a =       
*  ***  *  **    *  =     *

c =   ***
****      *****   =    *

e = ** 
  *   * *  *    = ** *

g = **  
* * ** * **     ** = ***

*   = c;
   =  *
  =  * *

** * =  
*  =  
* =     *


   * = ** * * *  *******
  *** ******  *      * 

  ** **
}

Comments

prog.c: In function 'main':
prog.c:4:19: error: variable 'h' set but not used [-Werror=unused-but-set-variable]
 int a,b,c,d,e,f,g,h,v,swap,temp,sum;
                   ^
cc1: all warnings being treated as errors

Answer 4

Hidden content!
**  * * 
* 
   *    *   ***  ***     
**  * * ***** * **  * ***  *
a =  *   
 *  *  * *** * **  *     =   * *

c = **  
****** **** *  **     = * ***

e =  
     **  **  * =    * 

g = *
 * *  ** * ****** =  * 

  =  
** = **
 * =  *

 **  =   
* =  *
   =    


* *  = *  *         * **
* ** *****   *****  **** ****

* *  *
*

Comments

prog.c: In function 'main':
prog.c:4:1: error: implicit declaration of function 'scanf' [-Werror=implicit-function-declaration]
 scanf("%d",&v);
 ^~~~~
prog.c:4:1: error: incompatible implicit declaration of built-in function 'scanf' [-Werror]
prog.c:4:1: note: include '<stdio.h>' or provide a declaration of 'scanf'
prog.c:27:1: error: implicit declaration of function 'printf' [-Werror=implicit-function-declaration]
 printf("%d",sum);
 ^~~~~~
prog.c:27:1: error: incompatible implicit declaration of built-in function 'printf' [-Werror]
prog.c:27:1: note: include '<stdio.h>' or provide a declaration of 'printf'
prog.c:3:19: error: variable 'h' set but not used [-Werror=unused-but-set-variable]
 int a,b,c,d,e,f,g,h,v,swap,temp,sum;
                   ^
cc1: all warnings being treated as errors