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