Randomized select

DAA_Randomized_Select.cpp

@@ -0,0 +1,99 @@
+#include<iostream>
+#include<stdlib.h>
+using namespace std;
+template<class t>
+class random
+{
+public:
+	t a[500];
+	int count, n;
+	void input();
+	void display();
+	int qsort(t a[], int p, int r);
+	int partition(t a[], int p, int r);
+	int randomSelect(t a[], int p, int r, int i);
+};
+template<class t>
+void random<t>::input()
+{
+	int i;
+	cout << "Enter the no of elements" << endl;
+	cin >> n;
+	for (i = 1;i <= n; i++)
+		a[i] = rand() % 100;
+}
+template<class t>
+void random<t>::display()
+{
+	for (int i = 1; i <= n;i++)
+		cout << a[i] << " ";
+}
+template<class t>
+int random<t>::partition(t a[], int p, int r)
+{
+	int x, i, j, temp;
+	x = a[r];
+	i = p - 1;
+	for (j = p; j <= r - 1; j++)
+	{
+		if (a[j] <= x)
+		{
+			i = i + 1;
+			temp = a[j];
+			a[j] = a[i];
+			a[i] = temp;
+		}
+		count++;
+	}
+	temp = a[i+1];
+	a[i+1] = a[r];
+	a[r] = temp;
+	return i + 1;
+}
+template<class t>
+int random<t>::randomSelect(t a[], int p, int r, int i)
+{
+	int k, q;
+	if (p == r)
+		return a[p];
+	q = partition(a, p, r);
+	k = q - p + 1;
+	if (i == k)
+		return a[q];
+	else if (i < k)
+		return randomSelect(a, p, r, i);
+	else
+		return randomSelect(a, q + 1, r, k);
+}
+template<class t>
+int random<t>::qsort(t a[], int p, int r)
+{
+	int q, i;
+	if (p < r)
+	{
+		q = partition(a, p, r);
+		qsort(a, p, q - 1);
+		qsort(a, q + 1, r);
+	}
+	return count;
+}
+int main()
+{
+	int c;
+	char ch = 'y';
+	while (ch == 'y' || ch == 'Y')
+	{
+		random<int> o;
+		o.input();
+		cout << "\n The elements of the array are: ";
+		o.display();
+		o.count = 0;
+		c = o.qsort(o.a, 1, o.n);
+		cout << "count: " << c;
+		cout << "\n After Sorting =]: " << endl;
+		o.display();
+		cout << "\n Do you want to continue?(y/n)";
+		cin >> ch;
+	}
+	return 0;
+}