// Name: 
// Lab: 3
// CS 136 Spring 2000

import structure.*;  // see http://www.cs.williams.edu/~bailey/JavaStructures/documentation.html
import java.util.Random;	// will need a random number generator

public class Search

{
	// pre:
 	// post: returns the position
 	//       of the first occurrence of x if x is in the array A
 	//       and -1 otherwise

	public static int linearSearch (int[] A, int x)
	{
   		int i;
   		for (i = 0; (i < A.length) && (x != A[i]); i++);
   		if (i == A.length)
      		return -1;
   		else
      		return i;
	}

	// pre: the array A is sorted in non-decreasing order
	// post: returns the position
	// 	     of the first occurrence of x if x is in the array A
	//       and -1 otherwise

	public static int binarySearch (int[] A, int left, int right, int x)
	{
   		if (left >= right)
     	{
     		int compare = (left + right)/2;
    	  	if (x == A[compare])
     	    	return compare;
    	  	else
      	   		return -1;
     	}
   		else
      	{
         	int mid = (left + right) / 2;
         	if (x == A[mid])
            	return mid;
         	else
            	if (x < A[mid])
               		return binarySearch (A, left, mid-1, x);
            	else
               		return binarySearch (A, mid+1, right, x);
      	}
	}

	public static void main(String args[])
	{
   		System.out.println("Test your search algorithms thoroughly.  Try these and more...");
   		int[] a = {1,3,6,8,10,13,15,20,24,26,29,46,50};
   		System.out.println(" 26 was fount at: " + linearSearch(a, 26));
   		System.out.println(" 26 was fount at: " +
                               binarySearch(a, 0, a.length-1, 26));
                               
        System.out.println(" 1 was fount at: " + linearSearch(a, 1));
   		System.out.println(" 1 was fount at: " +
                               binarySearch(a, 0, a.length-1, 1));
                               
        System.out.println(" 50 was fount at: " + linearSearch(a, 50));
   		System.out.println(" 50 was fount at: " +
                               binarySearch(a, 0, a.length-1, 50));
                               
        System.out.println(" 0 was fount at: " + linearSearch(a, 0));
   		System.out.println(" 0 was fount at: " +
                               binarySearch(a, 0, a.length-1, 0));
                               
        System.out.println(" 52 was fount at: " + linearSearch(a, 52));
   		System.out.println(" 52 was fount at: " +
                               binarySearch(a, 0, a.length-1, 52));

	}

}