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