From b580b29b666e2347fcac4eb4cf54eb16b63ef9a3 Mon Sep 17 00:00:00 2001
From: Slone <50995948+Slone123c@users.noreply.github.com>
Date: Mon, 5 Dec 2022 19:08:24 +0800
Subject: [PATCH] Update binary_search.md

Left closed right closed interval bsearch using go
---
 docs/chapter_searching/binary_search.md | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/docs/chapter_searching/binary_search.md b/docs/chapter_searching/binary_search.md
index 5000b66..04dbba8 100644
--- a/docs/chapter_searching/binary_search.md
+++ b/docs/chapter_searching/binary_search.md
@@ -123,7 +123,24 @@ $$
 === "Go"
 
     ```go title="binary_search.go"
-
+    /* 二分查找（左闭右开） */
+    func binarySearch1(nums []int, target int) int {
+        // 初始化左闭右开 [0, n) ，即 i, j 分别指向数组首元素、尾元素+1
+        i, j := 0, len(nums)
+        // 循环，当搜索区间为空时跳出（当 i = j 时为空）
+        for i < j {
+            m := (i + j) / 2                // 计算中点索引 m
+            if nums[m] < target {           // 此情况说明 target 在区间 [m+1, j) 中
+                i = m + 1
+            } else if nums[m] > target {    // 此情况说明 target 在区间 [i, m) 中
+                j = m
+            } else {                        // 找到目标元素，返回其索引
+                return m
+            }
+        }
+        // 未找到目标元素，返回 -1
+        return -1
+    }
     ```
 
 === "JavaScript"