if/else/else if语句有什么问题？

Question

int main(){
unsigned int fstNumb = 0, sndNumb = 0;
cout << "Choose the first number: ";
cin >> fstNumb;
cout << "\nChoose the second number: ";
cin >> sndNumb;
cout << "\nNow click \'m\' to multiply, \'a\' to add or \'d\' to divide: ";
char option = '\0';
cin >> option; cout << "\n\n";
float result;
if (option == 'm'){
    result = fstNumb * sndNumb;
    cout << result;
} 
else if (option == 'a'){
    result = fstNumb + sndNumb;
    cout << result;
}
else if (option == 'd') {
    if (fstNumb || sndNumb == 0)
        cout << "Cannot divide with 0 :/";
    else {
        cout << "You want the " << fstNumb << " or " << sndNumb << " to be divided?\n";
        cout << "Press 1 for " << fstNumb << " or 2 for " << sndNumb;
        char option2 = '\0';
        cin >> option2;
        if (option2 == 1){
            cout << "\nYou chose " << fstNumb;
            cout << "\nWanna divide it by how much?: ";
            unsigned short division;
            cin >> division;
            if (division == 0){
                cout << "\nCannot divide by 0!";
            }
            else{
                result = fstNumb / division;
            }
        }
        else if (option2 == 2){
            cout << "\nYou chose " << sndNumb;
            cout << "\nWanna divide it by how much?: ";
            unsigned short division;
            cin >> division;
            result = sndNumb / division;
        }
        else
            cout << "You must choose one of those 2 numbers!\n";
    }
}
else
    cout << "That's none of the letters I asked you.\n";

}

(fstNumb || sndNumb == 0)即使没有整数0,如果总是显示,那么问题是什么？
请注意,我没有使用布尔变量,但我认为这应该不是问题.

Answer 1

if (fstNumb || sndNumb == 0) 与...不是一回事 if (fstNumb == 0 || sndNumb == 0)