Negative numbers not working

I have a program where the user inputs a line of numbers, and the two highest ones are displayed. It works fine, until negative values are entered at which point it shows 0 as the result. Can someone help?

Code:

---

#include <iostream>
using namespace std;
int main( ) {
int num = 0;
int highest = 0;
int secondhighest = 0;
int input = 0;
cout << "How many numbers? ";
        cin >> num;
        cin >> input;
        int input2 = input;
//        highest = input;
        // secondhighest = input;
for(int track = 0; track < num; track++)
{     
        if(track == 1) {
                input = input2;
                }
else {               
cin >> input;
}




if (input > highest) {                 
secondhighest = highest;
highest = input;       
}
else if (input > secondhighest) {
secondhighest = input;
}
}               
cout << endl;
cout << "Highest: " << highest << endl;
       
cout << "Second: " << secondhighest;       
}

---

Any help?

That's because your variables to hold the users highest and second highest input are initialized to 0. So if the user enters a negative number it won't be greater than 0, so the contents of the variable won't change.

In your other post I said that i initialized my variables to contain large negative numbers to prevent this from happening. I'm not sure what the largest number an int can hold is, but I'm sure a quick google will give you the right result.

Code:

---

#include <limits>

// and in main
int highest = std::numeric_limits<int>::min();
int secondhighest = std::numeric_limits<int>::min();

---

This would be the standard C++ way of doing it.

Yeah, but I wouldn't use such a thing, since it bakes in type specific dependencies. Picture what would need to be done if, for some reason, the variables need to be changed so they are of some other type.


Easier to initialise highest and secondhighest with the first two values input (and also write the code to cope if the user enters less than two values).

Quote:

---

Originally Posted by grumpy

Picture what would need to be done if, for some reason, the variables need to be changed so they are of some other type.

---

Typedef time!

Typedefs wouldn't work in all cases.

Consider what would happen if it was decided to use a "huge int" type (say a class named huge_int_type). Even if the implementer of such a type was to specialise std::numeric_limits<huge_int_type> appropriately (which is feasible) it would not necessarily be appropriate for std::numeric_limits<huge_int_type>::min() be provided.

numeric_limits for unsigned types are also not required to provide a min().