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