mirror of https://github.com/TheAlgorithms/C
43 lines
1.1 KiB
C
43 lines
1.1 KiB
C
#include <stdio.h>
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// Recursive Function- It returns location of x assumiung array arr[l..r] is
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// 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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{
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int mid = l + (r - l) / 2;
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// If element is present at middle
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if (arr[mid] == x)
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return mid;
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// If element is smaller than middle
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if (arr[mid] > x)
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return binarysearch(arr, l, mid - 1, x);
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// Else element is in right subarray
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return binarysearch(arr, mid + 1, r, x);
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}
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// 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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// give function an array to work with
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int arr[] = {2, 3, 4, 10, 40};
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// get size of array
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int n = sizeof(arr) / sizeof(arr[0]);
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// set value to look for
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int x = 10;
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// set result to what is returned from binarysearch
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int result = binarysearch(arr, 0, n - 1, x);
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// print out result
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(result == -1) ? printf("Element is not in the array\n")
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: printf("Element is present at index %d\n", result);
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return 0;
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}
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