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