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