//
// This is example code from Chapter 20.1.2 "Generalizing code" of
// "Programming -- Principles and Practice Using C++" by Bjarne Stroustrup
//

#include "../std_lib_facilities.h"

//------------------------------------------------------------------------------

double* get_from_jack(int* count);  // jack puts doubles into an array
// and returns the number of elements
// in *count
vector<double>* get_from_jill();    // Jill fills the vector

//------------------------------------------------------------------------------

double* high(double* first, double* last)
// return a pointer to the element in [first,last) that has the highest value
{
    double h = -1;
    double* high;
    for(double* p = first; p!=last; ++p)
		if (h<*p) {
			high = p;
			h = *high;
		}
    return high;
}

//------------------------------------------------------------------------------

void fct()
{
    int jack_count = 0;
    double* jack_data = get_from_jack(&jack_count);    
    vector<double>* jill_data = get_from_jill();    
    vector<double>& v = *jill_data;

    double* middle = &v[0]+v.size()/2;
    double* high1 = high(&v[0], middle);          // max of first half
    double* high2 = high(middle, &v[0]+v.size()); // max of second half

    cout << "max of first half: " << *high1
         << "; max of second half: " << *high2;

    delete[] jack_data;
    delete jill_data;
}

//------------------------------------------------------------------------------

int main()
{
    fct();
}

//------------------------------------------------------------------------------

double* get_from_jack(int* count)
{
    if (!count)
        return 0;

    const int n = 10;

    double* arr = new double[n];

    if (arr)
    {
        *count = n;

        for (int i = 0; i < n; ++i)
            arr[i] = i;
    }

    return arr;
}

//------------------------------------------------------------------------------

vector<double>* get_from_jill()
{
    const int n = 10;

    vector<double>* arr = new vector<double>(n);

    if (arr)
    {
        for (int i = 0; i < n; ++i)
            (*arr)[i] = i;
    }

    return arr;
}

//------------------------------------------------------------------------------

double* find_highest(vector<double>& v)
{
    double h = -1;
    double* high = 0;
    for (int i=0; i<v.size(); ++i)
        if (h<v[i]) high = &v[i];
    return high;
}

//------------------------------------------------------------------------------