Psuedo random numbers in a bubble sort.

Basically, I'm unsure of how to utilize the function rand(). All I want to do is create 20 random numbers, use a bubble sort on them, print the sorted list and the time it takes to sort it.

Code:

`#include <cstdlib>`

#include <iostream>

#include <ctime>

#include <cstdlib>

using std::cout;

using std::endl;

int main()

{

void bubble(int a[], int n);

void print(int a[], int n);

int random(int n);

int n = 20;

int a[n];

a[n] = random(n);

clock_t start = clock();

bubble(a, n);

clock_t end = clock();

print(a, n);

double time_elapsed = double(end - start)/CLOCKS_PER_SEC;

system("PAUSE");

}

void swap(int a, int b)

{

int temp;

temp = a;

a = b;

b = temp;

}

void bubble(int a[], int n)

{

int sorted = false;

int pass = 1;

while (pass < n && !sorted)

{

sorted = true;

for ( int i = 0; i <= n - pass - 1; i++)

{

if (a[i] > a[i + 1])

{

swap(a[i], a[i + 1]);

sorted = false;

}

}

pass = pass + 1;

}

}

void print(const int a[], int n)

{

for (int i = 0; i <= n; i++)

cout << a[i] << " " << endl;

}

int random(int n)

{

int a[n];

for (int i = 0; i <= n; i++)

a[i] = rand();

return a[n];

}