what's the error in this c++ code

Question

my friend wrote a c++ code, it's not working, and he came to me for help. the problem is that i don't know c++ :) i'm more interested in python and i don't want to learn c++ anytime soon, so i come here for help :) here's the code

#include<iostream>

using namespace std;

int main (){
    char a ;
    cin >> a ;
    switch (a) {
    case '+' :
        int x , y , result ;

        cout << "Enter A number >> " ;
        cin >> x ;
        cout << endl ;

        cout << "Enter A number >> " ;
        cin >> y ;
        cout << endl ;

        result = x+y ;

        cout << "The Answer Is >> " << result << endl ;
        break ;
    case '-' :
        int x , y , result ;

        cout << "Enter A number >> " ;
        cin >> x ;
        cout << endl ;

        cout << "Enter A number >> " ;
        cin >> y ;
        cout << endl ;

        result= x-y ;

        cout << "The Answer Is >> " << result << endl ;
        break ;
    default :
        cout << "Please choose the right operaions !" << endl ;
    }
    return 0 ;
}

Please indent your code, it is really hard work to read when it isn't. — Yacoby, Nov 13 '11 at 12:13
"Not working" is not a good error description. State any compiler errors and/or any runtime outputs together with your expected outputs. — thiton, Nov 13 '11 at 12:15

score 2 · Accepted Answer · answered Nov 13 '11 at 12:15

2

You are defining int x, y, result for multiple times within one statement block. Merge the definitions and move to the top of the function, then it will compile. Like:

char a;
int x, y, result;

answered Nov 13 '11 at 12:15

Ryan Li

9,020
7
33
62

1

... Or add braces `{` and `}` between the `case ?? :` and the `break ;` to scope those variables... – paercebal Nov 13 '11 at 12:19
@paercebal: the easiest solution, but doesn't look good here. :-) – Ryan Li Nov 13 '11 at 12:26

score 1 · Answer 2 · answered Nov 13 '11 at 12:21

 case '+' :
        int x , y , result ;

        cout << "Enter A number >> " ;
        cin >> x ;
        cout << endl ;

        cout << "Enter A number >> " ;
        cin >> y ;
        cout << endl ;

        result = x+y ;

        cout << "The Answer Is >> " << result << endl ;
        break ;

doesn't work but you can get it to compile by adding a scope:

 case '+' :
        {
           int x , y , result ;

           cout << "Enter A number >> " ;
           cin >> x ;
           cout << endl ;

           cout << "Enter A number >> " ;
           cin >> y ;
           cout << endl ;

           result = x+y ;

           cout << "The Answer Is >> " << result << endl ;
        }
        break ;

...

but code should be restructured since there is a lot of duplicate code.

score 0 · Answer 3 · answered Nov 13 '11 at 12:20

0

You declared int x,y and result of type int 2 times in the statement "switch". Declare them global variables or outside the switch statement(within main() function).

answered Nov 13 '11 at 12:20

Kanghu

561
1
10
23

score 0 · Answer 4 · edited May 23 '17 at 12:06

0

Defining variables inside the switch block does not work and here's why

edited May 23 '17 at 12:06

Community

1
1

answered Nov 13 '11 at 12:21

Aditya Sehgal

2,867
3
27
37

what's the error in this c++ code

4 Answers4