Question

Using Selection Sort on an any array of size 7, what will be the minimum/maximum number of comparisons and number of exchanges?

1 for i = 1 to A.length-1

2 for j = i+1 to A.length

3 if A[j] < A[i]

4 exchange A[i] with A[j]

Answer 1

Please find the code below .

In selection sort minimum and maximum number of comparisons and swapping is same in all case like worst best and average.

#include <iostream>
using namespace std;

int main()
{
   int array[7];
   for(int i=0;i<7;i++){
       array[i] = rand()%100;
   }
   cout<<"Before sorting"<<endl;
   for(int i=0;i<7;i++){
       cout<<array[i]<<" ";
   }
   cout<<endl;

   int numberOfComparision = 0;
   int numberOfExchng = 0;
   for(int i=0;i<6;i++){
       for(int j=i+1;j<7;j++){
           numberOfComparision++;
           if(array[j]<array[i]){
               numberOfExchng++;
               int tmp = array[i];
               array[i] = array[j];
               array[j] = tmp;
           }
       }
   }

   cout<<"After sorting"<<endl;
   for(int i=0;i<7;i++){
       cout<<array[i]<<" ";
   }

   cout<<" Number of comparision is : "<<numberOfComparision<<endl;
   cout<<"Number of exchanges is : "<<numberOfExchng<<endl;

   cout<<endl;

   return 0;
}

output: