From d31b918c9606cb62576bd69b16105cc1398c4bd8 Mon Sep 17 00:00:00 2001
From: Gleb Koval <gleb@koval.net>
Date: Fri, 5 Nov 2021 12:53:13 +0000
Subject: [PATCH] product-of-array-except-self

---
 product-of-array-except-self/sol.go | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 product-of-array-except-self/sol.go

diff --git a/product-of-array-except-self/sol.go b/product-of-array-except-self/sol.go
new file mode 100644
index 0000000..84ddff2
--- /dev/null
+++ b/product-of-array-except-self/sol.go
@@ -0,0 +1,18 @@
+package main
+
+// Time: O(n)
+// Space: O(1)
+func productExceptSelf(nums []int) []int {
+	l := len(nums)
+	answer := make([]int, l)
+	answer[0] = 1
+	for idx := 1; idx < l; idx++ {
+		answer[idx] = answer[idx-1] * nums[idx-1]
+	}
+	m := 1
+	for idx := l - 1; idx >= 0; idx-- {
+		answer[idx] *= m
+		m *= nums[idx]
+	}
+	return answer
+}