Added binary search recursion program

algorithms/searches/binary_search_recursion.py

@@ -0,0 +1,27 @@
+def binary_search(l,x,start,end):
+    #base case: 1 element in the list
+    if(start==end):
+        if(l[start]==x):
+            return start
+        else:
+            return -1
+    else:
+        #divide the array into halves
+        mid=(start+end)//2
+        #typecasting is changing data types
+        if(l[mid]==x):
+            return mid
+        elif(l[mid]>x):
+            #first half
+            return binary_search(l,x,start,mid-1)
+        else:
+            #right half
+            return binary_search(l,x,mid+1,end)
+
+l=[20,45,60,60,90]
+x=int(input("What element do you need to find? "))
+index=binary_search(l,x,0,len(l)-1)
+if(index==-1):
+    print("Not found")
+else:
+    print("Element found at : ",index+1)