Sorting Agorithm - Assignment No 1

Q1. Using any two sorting algorithms, sort arrays of length 100, 1000, 10000. Calculate the time taken by the algorithm for sorting the arrays of given lengths. Ans:     Selection Sort:

Selection sort is a simple sorting algorithm. This sorting algorithm is an in-place comparison-based algorithm in which the list is divided into two parts, the sorted part at the left end and the unsorted part at the right end. Initially, the sorted part is empty and the unsorted part is the entire list.

Program:

#include <iostream>
#include <stdlib.h>
#include <bits/stdc++.h>
using namespace std;
void Min(int *a,int &k,int n,int &loc){
   int mini = a[k];
   loc = k;
   for(int j=k+1;j<n;j++){
       if(mini > a[j]){
           mini = a[j];
           loc = j;
       }
   }
}
int main()
{
   int n = 1000; // size of array it can be changed
   int k=0,loc=0,temp,i;
   int a[n];
   clock_t sTime, eTime;
   // filling array with random numbers
   for(i=0;i<n;i++){
       int val = rand()%1000;
       a[i] = val;
   }
   // printing unsorted array
   cout<<"Random Numbers Array "<<endl;
   for(i=0;i<n;i++){
           cout<<a[i]<<" ";
   }
   cout<<endl<<endl<<endl;
   // sorting array with selection sort
   cout<<"Sorting Array Using Selection Sort... "<<endl;
   sTime = clock();
   //selection sort start
   for(k=0;k<n;k++){
       Min(a,k,n,loc);
       temp = a[k];
       a[k] = a[loc];
       a[loc] = temp;
   }
   //selection sort end
   eTime = clock();
   double time_taken = double(eTime - sTime) / double(CLOCKS_PER_SEC);
   cout << "Array of "<<n<<" numbers sorted in "
           << fixed<< time_taken << setprecision(5);
   cout << " sec " << endl<<endl<<endl;
   for(i=0;i<n;i++){
           cout<<a[i]<<" ";
   }
   return 0;
}

Outputs:

1. Array of 100 Numbers

In the figure, time taken for 100 numbers is so much short that’s why it is 0.000000 sec.

Figure 1 Sorting 100 Numbers

1. Array of 1000 Numbers

In the figure, time taken for 1000 numbers is 0.001000 sec.