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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*      *** **** *  *    *        * **  **  ***** 
**   ** ** ** **  * * ** * ** ***  ** * *** * *   ***   ** **  ****** ******* * *   **            
   *  *    *  ** **** **   * **** ****    **  *  **  **  *  ********* ** *** *
**        ** *** * **     * **** ***   ** * *    * ***  ***          * *  *    **       
  * *** * **  *         *** *  * *  ** ******* * * **
    *  ** *   ** ***  ** *  ** *     *    *      *****   **  *  ***    **  ** ;
* * *  *    *** ** **  ** ** ** 
  ***  * ***  *     * **   ** *  **  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