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