54 lines
1.4 KiB
C
54 lines
1.4 KiB
C
// C# implementation of recursive Binary Search
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using System;
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class GFG
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{
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// Returns index of x if it is present in
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// arr[l..r], else return -1
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static int binarySearch(int []arr, int l,
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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()
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{
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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 = binarySearch(arr, 0, n-1, x);
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if (result == -1)
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Console.WriteLine("Element not present");
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else
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Console.WriteLine("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 Sam007.
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