Java Applets Centre

Binary Search

Description
This applet demonstrates the binary search algorithm using a simple array. The algorithm takes O(log n) time in the worst case.

Create: Type a value between 3 and 19 in the text field, and click the "Create" button to construct an array of that size. The array is populated with randomly generated numbers sorted in ascending order.

Search: Type a value to be searched in the text field, and click the "Search" button.

Code (Binary search on a simple array)

boolean binarySearch(int key){
int first,last,mid = 0;
boolean found = false;
first=0; last=size-1;
while((!found) && (first <= last)){
   mid=first+(last-first)/2;
   if(arr[mid]==key) found=true;
   else if(key < arr[mid]) last=mid-1;
   else if(key > arr[mid]) first=mid+1;
}
return found;
}

Data Structures and Algorithms
Java Applets Centre

R. Mukundan
Department of Computer Science
University of Canterbury
Private Bag 4800, Christchurch
New Zealand.