Create exponentiation.py

Author: X0rD3v1L

exponentiation.py

@@ -0,0 +1,13 @@
+'''Efficient approach'''
+
+def bin_pow(a,n):
+	res = 1
+	while(n>0):
+		if n&1:
+			res = res * a
+		a = a * a
+		n >>= 1
+	return res
+print(bin_pow(2101010,32)) #20782597351780148360705447543438026166282198412508937706220746225693908693563681788663888827908012942663696008670876015403914749631306435949260373147394419808970340368320100000000000000000000000000000000
+
+'''  Time complexity : O(log n) '''