From 1360e366bf056d9f27aea46e0ade099342173460 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=9B=B7=E7=B3=BB=E6=B3=A1=E6=B3=A1?=
 <bubble_yang@yeah.net>
Date: Fri, 1 Nov 2019 10:27:30 +0800
Subject: [PATCH] Add Solution2.go for 0069.Sqrt(x)

---
 solution/0069.Sqrt(x)/Solution2.go | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
 create mode 100644 solution/0069.Sqrt(x)/Solution2.go

diff --git a/solution/0069.Sqrt(x)/Solution2.go b/solution/0069.Sqrt(x)/Solution2.go
new file mode 100644
index 0000000000000..c4379d8b011b1
--- /dev/null
+++ b/solution/0069.Sqrt(x)/Solution2.go
@@ -0,0 +1,14 @@
+func mySqrt(x int) int {
+	precision := 0.9 // 计算精度, 但 LeetCode 中要求返回 int 所以可以偷懒将误差 < 0.9 即可(不使用 1.0 是因为浮点型的精度问题), 追求精度可使用 0.0001
+	guess, check := 1.0, 0.0
+calc:
+	guess = (float64(x)/guess + guess) / 2
+	check = guess*guess - float64(x)
+	if check < 0 {
+		check = 0 - check
+	}
+	if check > precision {
+		goto calc
+	}
+	return int(guess)
+}