//DISPLAY 7.12 Sorting an Array
//Tests the procedure sort.
#include <iostream>
#include <vector>
#include <string>
using namespace std;
void fill_array(vector<string> &a);
//Precondition: size is the declared size of the array a.
//Postcondition: number_used is the number of values stored in a.
//a[0] through a[number_used - 1] have been filled with
//nonnegative integers read from the keyboard.

void sort(vector<string> &a);
//Precondition: number_used <= declared size of the array a.
//The array elements a[0] through a[number_used - 1] have values.
//Postcondition: The values of a[0] through a[number_used - 1] have
//been rearranged so that a[0] <= a[1] <= ... <= a[number_used - 1].

void swap_values(string& v1, string& v2);
//Interchanges the values of v1 and v2.

int index_of_smallest(const vector<string> a, int start_index);
//Precondition: 0 <= start_index < number_used. Referenced array elements have
//values.
//Returns the index i such that a[i] is the smallest of the values
//a[start_index], a[start_index + 1], ..., a[number_used - 1].

int main( )
{
    cout << "This program sorts numbers from lowest to highest.\n";

    vector<string> sample_array;
    fill_array(sample_array);
    sort(sample_array);

    cout << "In sorted order the numbers are:\n";
    for (int index = 0; index < sample_array.size(); index++)
        cout << sample_array[index] << " ";
    cout << endl;

    return 0;
}

//Uses iostream:
void fill_array(vector<string> a)
{
    string q = "3";
    a.pushback(q);
    string w = "2";
    a.pushback(w);
    string e = "1";
    a.pushback(e);
}

void sort(vector<string>a)
{
    int index_of_next_smallest;

 //<The rest of the definition of fill_array is given in Display 7.9.>
    for (int index = 0; index < a.size() - 1; index++)
    {//Place the correct value in a[index]:
        index_of_next_smallest =
                     index_of_smallest(a, index);
        swap_values(a[index], a[index_of_next_smallest]);
        //a[0] <= a[1] <=...<= a[index] are the smallest of the original array
        //elements. The rest of the elements are in the remaining positions.
    }
}


void swap_values(string& v1, string& v2)
{
    string temp;
    temp = v1;
    v1 = v2;
    v2 = temp;
}


int index_of_smallest(const int a[], int start_index, int number_used)
{
    int min = a[start_index],
        index_of_min = start_index;
    for (int index = start_index + 1; index < number_used; index++)
        if (a[index] < min)
        {
            min = a[index];
            index_of_min = index;
            //min is the smallest of a[start_index] through a[index]
        }

    return index_of_min;
}