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