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