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