49 lines
1.4 KiB
Java
49 lines
1.4 KiB
Java
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// Java implementation of recursive Binary Search
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class BinarySearch
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{
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// Returns index of x if it is present in arr[l..
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// r], else return -1
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int binarySearch(int arr[], int l, int r, int x)
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{
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if (r>=l)
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{
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int mid = l + (r - l)/2;
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// If the element is present at the
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// middle itself
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if (arr[mid] == x)
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return mid;
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// If element is smaller than mid, then
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// it can only be present in left subarray
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if (arr[mid] > x)
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return binarySearch(arr, l, mid-1, x);
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// Else the element can only be present
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// in right subarray
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return binarySearch(arr, mid+1, r, x);
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}
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// We reach here when element is not present
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// in array
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return -1;
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}
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// Driver method to test above
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public static void main(String args[])
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{
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BinarySearch ob = new BinarySearch();
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int arr[] = {2,3,4,10,40};
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int n = arr.length;
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int x = 10;
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int result = ob.binarySearch(arr,0,n-1,x);
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if (result == -1)
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System.out.println("Element not present");
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else
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System.out.println("Element found at index " +
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result);
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}
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}
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/* This code is contributed by Rajat Mishra */
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