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