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