Question

In this lab we are going to complete a profile of two sorting algorithms by running some tests to collect empirical data.

1. First we need to be able to generate some random integers. You can do this by including the following library :

#include 

Now first run the following to generate a seed :

srand (time(NULL))

You can then generate a random number using the function

rand()

2. We will use two sort algorithms - Selection Sort and Bubble Sort running on a vector v with n elements.

//selection sort
for (i = 0; i < n-1; i++)
    for (j = i+1; j < n; j++)
        if (v[i] > v[j])
            swap(v[i], v[j])

//bubble sort
for (i = n-1; i > 0; i--)
    for (j = 0; j < i; j++)
        if (v[j] > v[j+1])
            swap(v[j], v[j+1])

You should write two functions - one for each algorithm - to accept the vector and then sort the vector.

3. Test each function by creating a vector loaded with random numbers and running your sort functions. Make sure the functions are correctly sorting the vectors.

4. Next we want to time the functions. To do so we need a library :

#include-

Declare two variables :

clock_t start, finish;

And you can get the time used by the function with :

start=clock();
selsort(v);
finish=clock();
cout << "cpu time= " << finish-start;

You can see a full program here. 

THE FULL PROGRAM:

#include 
#include 
#include 
#include 

using namespace std;

void selsort(vector& v)
{
        for (int i = 0; i < v.size(); i++)
          for (int j = i+1; j < v.size(); j++)
              if (v[i] > v[j])
              { int t =v[i];
                v[i]=v[j];
                v[j]=t;
              }
}

int main()
{
        clock_t start, finish;
        srand (time(NULL));
        vector v;
        int n=0;
        cout << "Enter size of input :" ;
        cin >> n;
       

for (int i=0; i<n; i++)
                v.push_back(rand());
        start=clock();
        selsort(v);
        finish=clock();
        cout << "time= " << finish-start;
}

5. For each sort algorithm run 5 tests for input lengths 1000, 2000, 3000, ...,10000 and record the median result. You should therefore have 10 time samples for each algorithm

Answer 1

If you have any doubts, please give me comment...

#include <iostream>

#include <vector>

#include <cstdlib>

#include <ctime>

using namespace std;

void selsort(vector<int> &v) {

for (int i = 0; i < v.size(); i++)

for (int j = i + 1; j < v.size(); j++)

if (v[i] > v[j]) {

int t = v[i];

v[i] = v[j];

v[j] = t;

}

}

int main() {

clock_t start, finish;

srand(time(NULL));

vector<int> v;

int n = 0;

cout << "Enter size of input :";

cin >> n;

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

v.push_back(rand());

start = clock();

selsort(v);

finish = clock();

cout << "time= " << finish - start<<endl;

}