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

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#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

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#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