HELP WITH SIMPLE CALCULATOR!!!

[Legoisfun123]

I tried to make a calculator (which I thought would be easy) but then I encountered a problem. This is the code:

#include <iostream>

using namespace std;

int main()
{
int a;
int b = 0;
int result;

cout << "Enter a calculation: \n";
cin >> a;

result = a + b;

cout << "The answer is: " << result << endl;
cout << " \n";

return 0;
}

If I for example write 7+8, the answer I get is 7 (which is not correct). Test it if you want.

[S G H]

Step your program.
Step by step, you'll understand "a" can only store a value.
So, inserting 7+8, "a" will only store the first valid numeric value (7).
Also, for logic's sake, "b" was 0 and was not into any operation. You can't expect "b" to have a different value.

#include <iostream>

int main()
{
    int a;
    int b;
    int result;
    char operation;
    bool valid = 1;
    std::cin >> a >> operation >> b;
    switch(operation)
    {
        case '+':
            result = a+b;
            break;
        case '-':
            result = a-b;
            break;
        case '*':
            result = a*b;
            break;
        case '/':
            result = a/b;
            break;
        default:
            valid = 0;
            std::cout << "Invalid Operation" << std::endl;
    }
    if(valid)
        std::cout << result << std::endl;
    return 0;
}