75 lines
1.3 KiB
Java
75 lines
1.3 KiB
Java
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import java.util.Scanner;
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/**
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* Implements a Binary Search in Java
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*
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* @author unknown
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*/
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class BinarySearch
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{
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/**
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* This method implements the Binary Search
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*
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* @param array The array to make the binary search
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* @param key The number you are looking for
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* @param lb The lower bound
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* @param up The upper bound
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* @return the location of the key
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**/
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public static int BS(int array[], int key, int lb, int ub)
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{ if (lb>ub)
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{
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return -1;
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}
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int mid=(lb+ub)/2;
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if (key<array[mid])
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{
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return (BS(array, key, lb, mid-1));
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}
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else if (key>array[mid])
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{
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return (BS(array, key, mid+1, ub));
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}
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else
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{
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return mid;
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}
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}
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/**
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* This is the main method of Binary Search
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*
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* @author Unknown
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* @param args Command line parameters
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*/
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public static void main(String[] args)
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{
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Scanner input=new Scanner(System.in);
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int array[]=new int[10] ;
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int key;
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//Input
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System.out.println("Enter an array of 10 numbers : ");
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for (int i=0; i<10 ;i++ )
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{
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array[i]=input.nextInt();
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}
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System.out.println("Enter the number to be searched : ");
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key=input.nextInt();
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int index=BS(array, key, 0, 9);
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if (index!=-1)
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{
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System.out.println("Number found at index number : " + index);
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}
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else
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{
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System.out.println("Not found");
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}
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}
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}
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