Recursive Sort Example, C++ (clang)

Recursive Sort Example

// Example from Lecture 6 in class on recursive functions

#include <iostream>
#include <stdlib.h> // rand srand
using namespace std;

void recursiveSort(int *array, int n) 
{
    for (int i=0; i<10-n; i++) cout << "   ";
    cout << "Entering into recursiveSort:  n = " << n << ", Address of array = " << array << endl;
    if (n==1) {
        return;
    }
    // find smallest thing in the array, and put it first
    int smallIndex = 0; int smallValue = array[0];
    for (int i=1; i<n; i++) {
        if (array[i] < smallValue) {
            smallValue = array[i];
            smallIndex = i;
        }   
    }
    // swap smallest value with first value
    array[smallIndex] = array[0];
    array[0] = smallValue;
    // make recursive call, note the change of the arguement values
    array++;
    n -= 1;
    recursiveSort(array,n);
    for (int i=0; i<10-n; i++) cout << "   ";
    cout << "Returning from recursiveSort: n = " << n << ", Address of array = " << array << endl;
    return;
}

int main()
{
    int n, *array;
    cout << "Enter n: ";
    cin >> n;
    // create array of that size
    array = new int[n];
    cout << endl << "n = " << n << endl << endl;
    srand(1111);
    cout << "Initial array = ";
    for (int i=0; i<n; i++) {
        array[i] = rand() % 100;
        cout << array[i] << " ";
    }
    cout << endl;
    recursiveSort(array, n);
    cout << "Sorted array = ";
    for (int i=0; i<n; i++) {
        cout << array[i] << " ";
    }
    cout << endl;  
    return 0;
}


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