Thread: Need a hint as to how to make a program that prints two highest numbers from user inp

You cannot actually implement whiteflags' suggestion in post #14 unless you store the numbers in the array, or rather unreasonably expect the user to enter the same input a second time.

If your code for finding the highest works fine, then finding the second highest is easy: whenever you find a new highest, the previous highest must be second highest thus far.

You need to indent properly and add some whitespace to make it more readable:

Code:

#include <iostream>
using namespace std;
int main()
{
	int number;
	int othvar;
	int highest = 0;
	int second = 0;

	cout << "How many numbers? ";
	cin >> number;
	cin >> othvar;

	int rec = othvar;
	second = othvar;

	for (int track = 1; track < number; track++)
	{
		cin >> othvar;
		if (rec < othvar)
			rec = othvar;
		if (second < othvar && second < rec)
			second = othvar;
	}

	highest = rec;
	int sprint = second;
	cout << endl;

	cout << "Highest: " << highest;
	cout << endl;
	cout << "Second: " << sprint;
}

Your logic flawed, and that's why it won't work. Grab a debugger and step through it or step through it manually. If I give you the sequence 1, 5, 3, why does it fail?

Originally Posted by Kelton2

And how would I find the previous highest? Doing second = othvar would just make the output the same.

You already know the previous highest: it is by definition the highest before you found a number higher than it. This is why I say that "if your code for finding the highest works fine, then finding the second highest is easy". It is so easy, in fact, that you don't have to do anything at all besides recording it!

Look, if you don't get the logic such that you can implement an algorithm, try out concrete examples.

Originally Posted by Kelton2

it still doesn't print the correct result for every combination. What am I still missing?

Your code is clearly wrong, but it only becomes clear when you indent it properly:

Code:

#include <iostream>

using namespace std;

int main() {
    int number;
    int othvar;
    int highest = 0;
    int second = 0;
    cout << "How many numbers? ";
    cin >> number;
    cin >> othvar;
    int rec = othvar;

    for(int track = 1; track < number; track++) {
        cin >> othvar;
        second = rec;
        if(rec < othvar) {
            rec = othvar;
        }
    }
    highest = rec;
    int sprint = second;
    cout << endl;
    cout << "Highest: " << highest;
    cout << endl;
    cout << "Second: " << sprint;
}

Notice that you are assigning to second on every iteration. Frankly, you are using too many variables. You only need variables for the highest, second highest, and the current input. Get rid of what is unnecessary, and declare your variables near first use.

Thinking about it further (I experimented with the logic myself with concrete examples), my claim is a mistake: that is, if the second highest comes after the highest, you will not find it if you only assume that the previous highest is the second highest. So you do have to check for the second highest separately.

Originally Posted by Kelton2

OK, so how would I check for the second highest then? What would the check be?

Are you listening?

Originally Posted by laserlight

Look, if you don't get the logic such that you can implement an algorithm, try out concrete examples.

Originally Posted by Kelton2

OK, so how would I check for the second highest then? What would the check be?

Something like this:

Code:

if (input > highest) {
    second_highest = highest;
    highest = input;
} else if (input > second_highest) {
    second_highest = input;
}

Looks like we have another "do my homework for me".

Originally Posted by Kelton2

Still not working:

Indent your code properly and then explain to us, line by line, what the for loop does. When you do so, the reason why your code does not work will become obvious.

Oh, and get rid of rec and sprint.