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