How to search element in Character Array using Index in Java?
Declaration :
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public static int binarySearch(char[] a, int fromIndex, int toIndex, char key) |
Explanation :
Purpose | The java.util.Arrays.binarySearch(char[] a int fromIndex int toIndex char key) method searches a range of the specified array of chars for the specified value using the binary search algorithm. The range must be sorted before making this call.If it is not sorted the results are undefined. |
Parameters | a ===> This is the array to be searched. |
fromIndex ===> This is the index of the first element (inclusive) to be searched. | |
toIndex ===> This is the index of the last element (exclusive) to be searched. | |
key ===> This is the value to be searched for. | |
Return Value | This method returns index of the search key if it is contained in the array else it returns (-(insertion point) - 1). The insertion point is the point at which the key would be inserted into the array; the index of the first element in the range greater than the key or toIndex if all elements in the range are less than the specified key. |
Exception | IllegalArgumentException — if fromIndex > toIndex ,ArrayIndexOutOfBoundsException — if fromIndex < 0 or toIndex > a.length |
Java Program : Example
Below example will explain java.util.Arrays.binarySearch() method.
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package com.c4learn; import java.util.Arrays; public class ArrayDemo { public static void main(String[] args) { // Initialize unsorted char array char arr[] = {'t', 'q', 's', 'r','p'}; // Sorting array Arrays.sort(arr); // Printing Sorted Array List System.out.println("The sorted char array is:"); for (char ch : arr) { System.out.println("Character = " + ch); } // Enter the character to be searched char val = 't'; // Entering the range of index int index = Arrays.binarySearch(arr,1,5,val); System.out.println("The index of t is : " + index); } } |
Output of Program :
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The sorted char array is: Character = p Character = q Character = r Character = s Character = t The index of t is : 4 |