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