feat: commit solution 169

Author: lxlxw

_sidebar.md

@@ -7,23 +7,24 @@
   - [贡献者列表](contributor.md)
 
 - 📚  题目列表
-  - [1.两数之和　✅](solution/1-99/0001.two-sum/)
+  - [1.两数之和](solution/1-99/0001.two-sum/)
   - [2.两数相加](solution/1-99/0002.add-two-numbers/)
-  - [7.整数反转　✅](solution/1-99/0007.reverse-integer/)
-  - [9.回文数　✅](solution/1-99/0009.palindrome-number/)
-  - [13.罗马数字转整数 ✅](solution/1-99/0013.roman-to-integer/)
-  - [20.有效的括号 ✅](solution/1-99/0020.valid-parentheses/)
-  - [21.合并两个有序链表 ✅](solution/1-99/0021.merge-two-sorted-lists/)
-  - [26.删除排序数组中的重复项 ✅](solution/1-99/0026.remove-duplicates-from-sorted-array/)
-  - [27.移除元素 ✅](solution/1-99/0027.remove-element/)
-  - [28.实现 strStr() ✅](solution/1-99/0028.implement-strstr/)
-  - [35.搜索插入位置 ✅](solution/1-99/0035.search-insert-position/)
-  - [66.加一 ✅](solution/1-99/0066.plus-one/)
-  - [83.删除排序链表中的重复元素 ✅](solution/1-99/0083.remove-duplicates-from-sorted-list/)
-  - [88.合并两个有序数组 ✅](solution/1-99/0088.merge-sorted-array/)
-  - [125.验证回文串 ✅](solution/100-199/0125.valid-palindrome/)
-  - [217.存在重复元素 ✅](solution/200-299/0217.contains-duplicate/)
-  - [219.存在重复元素 II ✅](solution/200-299/0219.contains-duplicate-ii/)
+  - [7.整数反转](solution/1-99/0007.reverse-integer/)
+  - [9.回文数](solution/1-99/0009.palindrome-number/)
+  - [13.罗马数字转整数](solution/1-99/0013.roman-to-integer/)
+  - [20.有效的括号](solution/1-99/0020.valid-parentheses/)
+  - [21.合并两个有序链表](solution/1-99/0021.merge-two-sorted-lists/)
+  - [26.删除排序数组中的重复项](solution/1-99/0026.remove-duplicates-from-sorted-array/)
+  - [27.移除元素](solution/1-99/0027.remove-element/)
+  - [28.实现 strStr()](solution/1-99/0028.implement-strstr/)
+  - [35.搜索插入位置](solution/1-99/0035.search-insert-position/)
+  - [66.加一](solution/1-99/0066.plus-one/)
+  - [83.删除排序链表中的重复元素](solution/1-99/0083.remove-duplicates-from-sorted-list/)
+  - [88.合并两个有序数组](solution/1-99/0088.merge-sorted-array/)
+  - [125.验证回文串](solution/100-199/0125.valid-palindrome/)
+  - [169.多数元素](solution/100-199/0169.majority-element/)
+  - [217.存在重复元素](solution/200-299/0217.contains-duplicate/)
+  - [219.存在重复元素 II](solution/200-299/0219.contains-duplicate-ii/)
 
 
 

index-tags.md

@@ -32,6 +32,7 @@
 |  [88](https://leetcode-cn.com/problems/merge-sorted-array)  |  [合并两个有序数组](/solution/1-99/0088.merge-sorted-array/)  |  `数组`,`双指针`  |  <font color=green>简单</font>  |✅ |
 |  [217](https://leetcode-cn.com/problems/contains-duplicate)  |  [存在重复元素](/solution/200-299/0217.contains-duplicate/)  |  `数组`,`哈希表`  |  <font color=green>简单</font>  |✅ |
 |  [219](https://leetcode-cn.com/problems/contains-duplicate-ii)  |  [存在重复元素 ii](/solution/200-299/0219.contains-duplicate-ii/)  |  `数组`,`哈希表`  |  <font color=green>简单</font>  |✅ |
+|  [169](https://leetcode-cn.com/problems/majority-element)  |  [多数元素](/solution/100-199/0169.majority-element/)  |  `位运算`,`数组`,`分治算法`  |  <font color=green>简单</font>  |✅ |
 
 #### **哈希表**
 
@@ -79,6 +80,10 @@
 
 #### **位运算**
 
+|  题号  |  题解  |  标签  | 难度  | 是否解题 |
+| --- | --- | --- | --- | --- |
+|  [169](https://leetcode-cn.com/problems/majority-element)  |  [多数元素](/solution/100-199/0169.majority-element/)  |  `位运算`,`数组`,`分治算法`  |  <font color=green>简单</font>  |✅ |
+
 #### **树**
 
 #### **递归**
@@ -95,6 +100,10 @@
 
 #### **分治算法**
 
+|  题号  |  题解  |  标签  | 难度  | 是否解题 |
+| --- | --- | --- | --- | --- |
+|  [169](https://leetcode-cn.com/problems/majority-element)  |  [多数元素](/solution/100-199/0169.majority-element/)  |  `位运算`,`数组`,`分治算法`  |  <font color=green>简单</font>  |✅ |
+
 #### **回溯算法**
 
 #### **脑筋急转弯**

index-type.md

@@ -47,7 +47,7 @@
 |  [160](https://leetcode-cn.com/problems/intersection-of-two-linked-lists)  |  [相交链表](/solution/100-199/0160.intersection-of-two-linked-lists/)  |  `链表`  |  <font color=green>简单</font>  |
 |  [167](https://leetcode-cn.com/problems/two-sum-ii-input-array-is-sorted)  |  [两数之和 ii - 输入有序数组](/solution/100-199/0167.two-sum-ii---input-array-is-sorted/)  |  `数组`,`双指针`,`二分查找`  |  <font color=green>简单</font>  |
 |  [168](https://leetcode-cn.com/problems/excel-sheet-column-title)  |  [excel表列名称](/solution/100-199/0168.excel-sheet-column-title/)  |  `数学`  |  <font color=green>简单</font>  |
-|  [169](https://leetcode-cn.com/problems/majority-element)  |  [多数元素](/solution/100-199/0169.majority-element/)  |  `位运算`,`数组`,`分治算法`  |  <font color=green>简单</font>  |
+|  [169](https://leetcode-cn.com/problems/majority-element)  |  [多数元素](/solution/100-199/0169.majority-element/)  |  `位运算`,`数组`,`分治算法`  |  <font color=green>简单</font>  |✅ |
 |  [170](https://leetcode-cn.com/problems/two-sum-iii-data-structure-design)  |  [两数之和 iii - 数据结构设计](/solution/100-199/0170.two-sum-iii---data-structure-design/)  |  `设计`,`哈希表`  |  <font color=green>简单</font>  |
 |  [171](https://leetcode-cn.com/problems/excel-sheet-column-number)  |  [excel表列序号](/solution/100-199/0171.excel-sheet-column-number/)  |  `数学`  |  <font color=green>简单</font>  |
 |  [172](https://leetcode-cn.com/problems/factorial-trailing-zeroes)  |  [阶乘后的零](/solution/100-199/0172.factorial-trailing-zeroes/)  |  `数学`  |  <font color=green>简单</font>  |

solution/100-199/0169.majority-element/README.md

@@ -0,0 +1,56 @@
+# [169.多数元素](https://leetcode-cn.com/problems/majority-element/description/)
+
+
+### 题目描述
+
+<div class="notranslate"><p>给定一个大小为 <em>n </em>的数组，找到其中的多数元素。多数元素是指在数组中出现次数<strong>大于</strong>&nbsp;<code>⌊ n/2 ⌋</code>&nbsp;的元素。</p>
+
+<p>你可以假设数组是非空的，并且给定的数组总是存在多数元素。</p>
+
+<p>&nbsp;</p>
+
+<p><strong>示例&nbsp;1:</strong></p>
+
+<pre><strong>输入:</strong> [3,2,3]
+<strong>输出:</strong> 3</pre>
+
+<p><strong>示例&nbsp;2:</strong></p>
+
+<pre><strong>输入:</strong> [2,2,1,1,1,2,2]
+<strong>输出:</strong> 2
+</pre>
+</div>
+
+### 解题思路
+
+1. 利用hash表来实现
+
+### 代码实现
+
+<!-- tabs:start -->
+
+#### **Golang**
+```go
+func majorityElement(nums []int) int {
+	l := len(nums)
+	if l == 0 {
+		return 0
+	}
+	n := l/2 + l%2 // l%2为额外加个奇偶数的判断
+	numMap := make(map[int]int)
+	for _, v := range nums {
+		if _, ok := numMap[v]; ok {
+			numMap[v]++
+		} else {
+			numMap[v] = 1
+		}
+		if numMap[v] >= n {
+			return v
+		}
+	}
+	return -1
+}
+```
+
+
+<!-- tabs:end -->

solution/100-199/0169.majority-element/solution.go

@@ -0,0 +1,30 @@
+package leetcode
+
+/*
+ * @lc app=leetcode.cn id=169 lang=golang
+ *
+ * [169] 多数元素
+ */
+
+// @lc code=start
+func majorityElement(nums []int) int {
+	l := len(nums)
+	if l == 0 {
+		return 0
+	}
+	n := l/2 + l%2 // l%2为额外加个奇偶数的判断
+	numMap := make(map[int]int)
+	for _, v := range nums {
+		if _, ok := numMap[v]; ok {
+			numMap[v]++
+		} else {
+			numMap[v] = 1
+		}
+		if numMap[v] >= n {
+			return v
+		}
+	}
+	return -1
+}
+
+// @lc code=end

solution/100-199/0169.majority-element/solution_test.go

@@ -0,0 +1,28 @@
+package leetcode
+
+import (
+	"testing"
+)
+
+func TestMajorityElement(t *testing.T) {
+	var nums []int
+	var ret int
+
+	nums = []int{3, 2, 3}
+	ret = 3
+	if ret != majorityElement(nums) {
+		t.Fatalf("case fails: %v\n", ret)
+	}
+
+	nums = []int{2, 2, 1, 1, 1, 2, 2}
+	ret = 2
+	if ret != majorityElement(nums) {
+		t.Fatalf("case fails: %v\n", ret)
+	}
+
+	nums = []int{}
+	ret = 0
+	if ret != majorityElement(nums) {
+		t.Fatalf("case fails: %v\n", ret)
+	}
+}