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