Lab4

#include<iostream>
#include<time.h>

using namespace std;

class MyDoubleStack
{
private:
    double * _array = NULL;
    int _arraySize = -1;
    int _arrayPos = -1;

public:
    MyDoubleStack(int size)
    {
        _arraySize = size;
        _array = new double[_arraySize];
        for (int i = 0; i < _arraySize; i++) _array[i] = NAN;
        _arrayPos = -1;
    }

    ~MyDoubleStack()
    {
        delete[] _array;
        _array = NULL;
        _arraySize = -1;
        _arrayPos = -1;
    }

    void Push(double value)
    {
        if (!TryPush(value))
        {
            cout << "Can't push element. Maximum elements count reached." << endl;
            return;
        }
    }

    double Pop()
    {
        double res = NULL;
        if (!TryPop(&res))
        {
            cout << "Can't pop element. Stack is empty." << endl;
            return NAN;
        }
        return res;
    }

    bool TryPush(double value)
    {
        if (_arrayPos >= _arraySize-1) return false;
        _array[++_arrayPos] = value;
        return true;
    }

    bool TryPop(double * outValue)
    {
        if (_arrayPos <= -1) return false;
        *outValue = _array[_arrayPos];
        _array[_arrayPos] = NAN;
        _arrayPos--;
        return true;
    }

};

// http://stackoverflow.com/questions/2704521/generate-random-double-numbers-in-c
double fRand(double fMin, double fMax)
{
    double f = (double)rand() / RAND_MAX;
    return fMin + f * (fMax - fMin);
}



int main()
{
    srand(time(0));

    int arrSize = 10;

    double ** arr = new double*[arrSize];

    cout << "Array of ptr to doubles:" << endl;
    for (int i = 0; i < arrSize; i++)
    {
        arr[i] = new double(fRand(-10, 10));
        cout << *arr[i] << endl;
    }
    cout << endl;

    MyDoubleStack positives(arrSize), negatives(arrSize);

    for (int i = 0; i < arrSize; i++)
    {
        if (*arr[i] < 0) negatives.Push(*arr[i]);
        else positives.Push(*arr[i]);
    }

    double d;
    cout << "Stack of positives was:" << endl;
    while (positives.TryPop(&d)) cout << d << endl;
    cout << endl;

    cout << "Stack of negatives was:" << endl;
    while (negatives.TryPop(&d)) cout << d << endl;
    cout << endl;


    for (int i = 0; i < arrSize; i++)
    {
        delete arr[i];
    }
    delete[] arr;

    system("pause");

    return 0;
}