From 4eb5e0fc95cc107989b77434c19dd51ca28fbb9e Mon Sep 17 00:00:00 2001
From: YDZ <ydz627@gmail.com>
Date: Fri, 8 Nov 2019 23:16:07 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20problem=20704?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../0704. Binary Search/704. Binary Search.go | 16 +++++++
 .../704. Binary Search_test.go                | 48 +++++++++++++++++++
 Algorithms/0704. Binary Search/README.md      | 43 +++++++++++++++++
 3 files changed, 107 insertions(+)
 create mode 100644 Algorithms/0704. Binary Search/704. Binary Search.go
 create mode 100644 Algorithms/0704. Binary Search/704. Binary Search_test.go
 create mode 100755 Algorithms/0704. Binary Search/README.md

diff --git a/Algorithms/0704. Binary Search/704. Binary Search.go b/Algorithms/0704. Binary Search/704. Binary Search.go
new file mode 100644
index 00000000..59ee8d79
--- /dev/null
+++ b/Algorithms/0704. Binary Search/704. Binary Search.go	
@@ -0,0 +1,16 @@
+package leetcode
+
+func search704(nums []int, target int) int {
+	low, high := 0, len(nums)-1
+	for low <= high {
+		mid := low + (high-low)>>1
+		if nums[mid] == target {
+			return mid
+		} else if nums[mid] > target {
+			high = mid - 1
+		} else {
+			low = mid + 1
+		}
+	}
+	return -1
+}
diff --git a/Algorithms/0704. Binary Search/704. Binary Search_test.go b/Algorithms/0704. Binary Search/704. Binary Search_test.go
new file mode 100644
index 00000000..85c06368
--- /dev/null
+++ b/Algorithms/0704. Binary Search/704. Binary Search_test.go	
@@ -0,0 +1,48 @@
+package leetcode
+
+import (
+	"fmt"
+	"testing"
+)
+
+type question704 struct {
+	para704
+	ans704
+}
+
+// para 是参数
+// one 代表第一个参数
+type para704 struct {
+	nums   []int
+	target int
+}
+
+// ans 是答案
+// one 代表第一个答案
+type ans704 struct {
+	one int
+}
+
+func Test_Problem704(t *testing.T) {
+
+	qs := []question704{
+
+		question704{
+			para704{[]int{-1, 0, 3, 5, 9, 12}, 9},
+			ans704{4},
+		},
+
+		question704{
+			para704{[]int{-1, 0, 3, 5, 9, 12}, 2},
+			ans704{-1},
+		},
+	}
+
+	fmt.Printf("------------------------Leetcode Problem 704------------------------\n")
+
+	for _, q := range qs {
+		_, p := q.ans704, q.para704
+		fmt.Printf("【input】:%v       【output】:%v\n", p, search704(p.nums, p.target))
+	}
+	fmt.Printf("\n\n\n")
+}
diff --git a/Algorithms/0704. Binary Search/README.md b/Algorithms/0704. Binary Search/README.md
new file mode 100755
index 00000000..fd2c1b25
--- /dev/null
+++ b/Algorithms/0704. Binary Search/README.md	
@@ -0,0 +1,43 @@
+# [704. Binary Search](https://leetcode.com/problems/binary-search/)
+
+
+## 题目:
+
+Given a **sorted** (in ascending order) integer array `nums` of `n` elements and a `target` value, write a function to search `target` in `nums`. If `target` exists, then return its index, otherwise return `-1`.
+
+**Example 1:**
+
+    Input: nums = [-1,0,3,5,9,12], target = 9
+    Output: 4
+    Explanation: 9 exists in nums and its index is 4
+
+**Example 2:**
+
+    Input: nums = [-1,0,3,5,9,12], target = 2
+    Output: -1
+    Explanation: 2 does not exist in nums so return -1
+
+**Note:**
+
+1. You may assume that all elements in `nums` are unique.
+2. `n` will be in the range `[1, 10000]`.
+3. The value of each element in `nums` will be in the range `[-9999, 9999]`.
+
+
+## 题目大意
+
+
+给定一个 n 个元素有序的（升序）整型数组 nums 和一个目标值 target  ，写一个函数搜索 nums 中的 target，如果目标值存在返回下标，否则返回 -1。
+
+提示：
+
+- 你可以假设 nums 中的所有元素是不重复的。
+- n 将在 [1, 10000]之间。
+- nums 的每个元素都将在 [-9999, 9999]之间。
+
+
+## 解题思路
+
+
+- 给出一个数组，要求在数组中搜索等于 target 的元素的下标。如果找到就输出下标，如果找不到输出 -1 。
+- 简单题，二分搜索的裸题。