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