C++ Program to Perform Searching Based on Locality of Reference

Searching based on locality of reference, depends upon the memory access pattern data elements are reallocated.

Here linear searching method is used to search an element.

Algorithm

Begin
   int find(int *intarray, int n, int item)
   intialize comparisons = 0
   for i = 0 to n-1
      Increase comparisons
   if(item == intarray[i])
      Print element with its index
   break
   if(i == n-1)
      Print element not found
   return -1
   Print Total comparisons
   For j = i till i>0
      intarray[j] = intarray[j-1]
      intarray[0] = item
   return 0
End

Example

 Live Demo

#include<iostream>
using namespace std;
// A function to perform linear search.
// this method makes a linear search.
int find(int *intarray, int n, int item) {
   int i;
   int comparisons = 0;
   // navigate through all items
   for(i = 0;i<n;i++) {
      // count the comparisons made comparisons++;
      // if item found, break the loop
      if(item == intarray[i]) {
         cout<<"element found at:"<<i<<endl;
         break;
      }
      // If index reaches to the end then the item is not there.
      if(i == n-1) {
         cout<<"\nThe element not found.";
         return -1;
      }
   }
   printf("Total comparisons made: %d", comparisons);
   // Shift each element before matched item.
   for(int j = i; j > 0; j--)
      intarray[j] = intarray[j-1];
      // Put the recently searched item at the beginning of the data array.
      intarray[0] = item;
   return 0;
}
int main() {
   int intarray[20]={1,2,3,4,6,7,9,11,12,14,15,16,26,19,33,34,43,45,55,66};
   int i,n;
   char ch;
   // print initial data array.
   cout<<"\nThe array is: ";
   for(i = 0; i < 20;i++)
      cout<<intarray[i]<<" ";
   up:
   cout<<"\nEnter the Element to be searched: ";
   cin>>n;
   // Print the updated data array.
   if(find(intarray,20, n) != -1) {
      cout<<"\nThe array after searching is: ";
      for(i = 0; i <20;i++)
         cout<<intarray[i]<<" ";
   }
   cout<<"\n\nWant to search more.......yes/no(y/n)?";
   cin>>ch;
   if(ch == 'y' || ch == 'Y')
      goto up;
   return 0;
}

Output

The array is: 1 2 3 4 6 7 9 11 12 14 15 16 26 19 33 34 43 45 55 66
Enter the Element to be searched: 26
element found at:12
Total comparisons made: 13
The array after searching is: 26 1 2 3 4 6 7 9 11 12 14 15 16 19 33 34 43 45 55 66

Want to search more.......yes/no(y/n)?y

Enter the Element to be searched: 0

The element not found.

Want to search more.......yes/no(y/n)?n