Even and Odd Arrays

[GhibberishCode]

This code seems to assign an odd to the even array.

int main()
{

int range;
int score;
cout << "Please enter a number between 1 to 5: ";
cin >> range;
while (range < 1 || range > 5)
{
cout << "Please enter a number between 1 to 5: ";
cin >> range;
}

int createdArray[range];
for (int y = 0; y < range; y++)
{
cout << "Enter your " << (y + 1) << " score (1-100): ";
cin >> score;
while(score < 1 || score > 100 )
{
cout << "Enter your " << (y + 1) << " score (1-100): ";
cin >> score;
}
createdArray[y] = score;
}

cout << "\nArray the way user entered: ";
for (int y = 0; y < range; y++)
{
cout << createdArray[y] << " ";
}

cout << "\nArray in reverse order: ";
for (int y = (range-1); y >= 0; y--)
{
cout << createdArray[y] << " ";
}


cout << "\n\nFinding even scores stored in array.\n";

int remainder = 0;
int range1 = 0;
int range2 = 0;
int evenArray[range1];
int oddArray[range2];
for (int y = 0; y < range; y++)
{
remainder = createdArray[y] % 2;
if (remainder == 0)
{
evenArray[y]  = createdArray[y];
range1 = range1 + 1;
}
else
{
oddArray[y] = createdArray[y];
range2 = range2 + 1;
}
}
cout << "Even array: ";
for (int y = 0 ; y < range1; y++)
{
cout << evenArray[y] << " ";
}






return 0;
}

[rjphares]

I changed the index of even array and odd array. It was originally y.

for (int y = 0; y < range; y++)
    {
        remainder = createdArray[y] % 2;
        if (remainder == 0)
        {
            evenArray[range1] = createdArray[y];
            range1 = range1 + 1;
        }
        else
        {
            oddArray[range2] = createdArray[y];
            range2 = range2 + 1;
        }
    }

[dutch]

You've managed to use code tags but have somehow lost your indentation anyway! :-)

If you want to learn proper C++, then VLAs (variable-length arrays) are not legal. They were introduced into C in C99 and made optional in C11, so even the C people think they're a bad idea.

int createdArray[range];    // not standard C++ 

Instead we say this:

int* createdArray = new int[range];

//and you need to remember to delete it when you are done with it:
delete[] createdArray;

However, it's even better to use a vector:

vector<int> createdArray;

With a vector the memory allocation/deallocation is handled automatically and you can use the push_back() member function to append values to it.

Here you have another use of VLAs, but even if they were legal, this is incorrect:

int range1 = 0;
int range2 = 0;
int evenArray[range1];
int oddArray[range2];

That would create two arrays of 0 size. They won't automatically get bigger just because you increment range1 or range2. Also, in your algorithm, you are using j to index those arrays where you should be using range1 and range2 (i.e., the current size).

#include <iostream>
using namespace std;

int main()
{
    int range;
    while (true)
    {
        cout << "Please enter a number between 1 to 5: ";
        cin >> range;
        if (range >= 1 && range <= 5)
            break;
        cout << "That value is not in range.\n";
    }

    int* createdArray = new int[range];

    for (int i = 0; i < range; ++i)
    {
        int score;
        while (true)
        {
            cout << "Enter your " << (i + 1) << " score (1-100): ";
            cin >> score;
            if (score >= 1 && score <= 100)
                break;
        }
        createdArray[i] = score;
    }

    cout << "\nArray the way user entered: ";
    for (int i = 0; i < range; ++i)
        cout << createdArray[i] << ' ';

    cout << "\nArray in reverse order: ";
    for (int i = range; i-- > 0; )
        cout << createdArray[i] << ' ';

    cout << "\n\nFinding even scores stored in array.\n";

    int range1 = 0, range2 = 0;
    int* evenArray = new int[range]; // making them size of createdArray
    int* oddArray = new int[range];  // which will be big enough.

    for (int i = 0; i < range; ++i)
        if (createdArray[i] % 2 == 0)
            evenArray[range1++] = createdArray[i];
        else
            oddArray[range2++] = createdArray[i];

    cout << "Even array: ";
    for (int i = 0; i < range1; ++i)
        cout << evenArray[i] << ' ';
    cout << '\n';

    delete[] oddArray;
    delete[] evenArray;
    delete[] createdArray;
}

[cblack618]

Don’t listen to anything he is telling you

[dutch]

cblack618 is a liar and a cheat.
Do not help him..

* this is an automated response

[kbklpl21]

Hi cblack618, it's up to the person asking the question whether to listen or not, not up to you, so please leave if you're not here to help or to learn.

[cblack618]

Dude shut up

[dutch]

cblack618 is a liar and a cheat.
Do not help him.

* this is an automated response

[kbklpl21]

And you were asking others not to be rude to you

[cblack618]

i am specfically referring to dutch

[dutch]

cblack618 is a liar and a cheat.
Do not help him.

* this is an automated response