Invalid user-defined conversion: C++ error

Question

I am making a (very) simple calculator program in C++ using Code::Blocks as my IDE. I am experiencing a couple of errors in my program. Please take a look at my code and tell me what the mistake is. Thank you.

#include <iostream>
#include <limits>
#include <conio.h>

int num1;
char Operator;
int num2;


void sum() {
    std::cin >> num1; // User inputs first number
    std::cin >> Operator; // User inputs operator
    std::cin >> num2; // User inputs second number

    // These if statements identify the operator and perform the appropriate 
    // operation

    if ( Operator == '+' ) {
        std::cout << num1 + num2;
     }

    else if ( Operator == '-' ) {
        std::cout << num1 - num2;
    }

    else if ( Operator == '*' ) {
         std::cout << num1 * num2;
    }

    else if ( Operator == '/' ) {
        std::cout << num1 / num2;
    }

    else {
        std:: cout << "Incorrect value/s entered.";
    }
}

int main {
    std::cout << "Press q to quit the program.";

    while(1) {
        sum()

        if(ascii_value==113) { // For Q
            break;
        }
    }

    return 0;
}

Errors:

error: invalid user-defined conversion from 'std:: basic_ostream<char>' to 
'int' [-fpermissive]
error: expected unqualified-id before 'while'

I started learning C++ just four days ago, so please appreciate the fact that I don't know much about the errors. Also, I am unsure whether i need to include limits, so please tell me in the comments below.

Answer 1

int main is not a function declaration change it to

int main()

and sum() needs a semicolon. and in if(ascii_value==113), ascii_value is defined nowhere in the code