Merge pull request #12 from theycallmemac/patch-2

Create BinarySearch.c

BinarySearch.c

@@ -0,0 +1,39 @@
+#include <stdio.h>
+
+// Recursive Function- It returns location of x assumiung array arr[l..r] is present, otherwise -1
+
+int binarysearch(int arr[], int l, int r, int x)
+{
+   if (r >= l)
+   {
+        int mid = l + (r - l)/2;
+
+        // If element is present at middle
+        if (arr[mid] == x)  return mid;
+
+        // If element is smaller than middle
+        if (arr[mid] > x) return binarysearch(arr, l, mid-1, x);
+
+        // Else element is in right subarray
+        return binarysearch(arr, mid+1, r, x);
+   }
+
+   // When element is not present in array
+   return -1;
+}
+
+int main(void)
+{
+   // give function an array to work with
+   int arr[] = {2, 3, 4, 10, 40};
+   // get size of array
+   int n = sizeof(arr)/ sizeof(arr[0]);
+   //set value to look for
+   int x = 10;
+   // set result to what is returned from binarysearch
+   int result = binarysearch(arr, 0, n-1, x);
+   // print out result
+   (result == -1)? printf("Element is not in the array")
+                 : printf("Element is present at index %d", result);
+   return 0;
+}