37 lines
1.1 KiB
C++
37 lines
1.1 KiB
C++
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// C++ program to implement recursive Binary Search
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#include <bits/stdc++.h>
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using namespace std;
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// A recursive binary search function. It returns location of x in given array arr[l..r] is present,otherwise -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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int mid = l + (r - l) / 2;
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// If the element is present at the 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 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 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 in array
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return -1;
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}
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int main(void)
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{
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int arr[] = { 2, 3, 4, 10, 40 };
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int x = 10;
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int n = sizeof(arr) / sizeof(arr[0]);
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int result = binarySearch(arr, 0, n - 1, x);
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(result == -1) ? cout << "Element is not present in array"
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: cout << "Element is present at index " << result;
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return 0;
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}
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