From 0780e4b8ce1e1c6b65f04379253f145e9f557470 Mon Sep 17 00:00:00 2001
From: ridwanfathin <m.ridwanfathin@gmail.com>
Date: Thu, 8 Oct 2020 09:57:02 +0700
Subject: [PATCH] add fast pow: O(log n) exponent

---
 numerical/fast_pow.go | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 numerical/fast_pow.go

diff --git a/numerical/fast_pow.go b/numerical/fast_pow.go
new file mode 100644
index 0000000..1073c42
--- /dev/null
+++ b/numerical/fast_pow.go
@@ -0,0 +1,16 @@
+package numerical
+
+//O(log n) function for pow(x, y)
+func FastPow(n uint, power uint) uint {
+	var res uint = 1
+	for power > 0 {
+
+		if (power & 1) != 0 {
+			res = res * n
+		}
+
+		power = power >> 1
+		n = n * n
+	}
+	return res
+}