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()
{
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*** *** **  * **  ** ** * ***  * *  *    * *  
* ***     *** * *** ***   * * **** **   **** ** * * *  * ** * * **  ** *  *******             
 *  *  ***       *  * * ** ** *  * * **  **   * * ***  *   **  ** ** * ** * 
**  *   *   **   ** ** **  *** **     *    * *** ***     *   ** *  *  *** *** *** ***  **** *  *** ** **   *       
    * ** *    ** * *   **  **  ** ****  *  * ** *****    
 *  * * * *  *   **      * * *  * *** *   *** * * **  ** *   ****   *  *  * **  **  ;
* *** *  * ** * *  * *** ** 
*    *       *  *  * ***** * ******* 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