/*
 This is a program that implements binary search. 

 Laura Toma
*/


public class BinSearch {
	
	public static void main (String args[]) {
		
		final int SIZE = 100; 

		ReadStream r = new ReadStream(); 
		
		//declare and allocate array
		int[] a = new int [SIZE]; 

		//initialize array in increasing order
		int i=0; 
		while (i < SIZE) {
			a[i] =i;
			i++;
		}
		System.out.println("test array size: " + SIZE);
	

		//read target
		int target; 
		System.out.print("Enter target: ");
		target = r.readInt();
		r.readLine();

		//binary search for target in a[]

		//two indices that repr the portion of a[] we are currently looking at 
		int left, right;
		int middle=0; //this represents the middle between left and right
		boolean found; 

		//initial values
		left = 0; right = SIZE-1;
		found = false; 

		while (right >= left && found == false) {
			middle = (left + right)/2;
			if (a[middle] == target) found = true; 
			if (a[middle] < target) left = middle +1; 
			if (a[middle] > target) right = middle -1; 
		}

		if (found == true) 
			System.out.println("Found at position " + middle);
		else 
			System.out.println("Not found");

		
	} // end of main
	
} // end of class