feat: commit solution 219

Author: lxlxw

solution/200-299/0219.contains-duplicate-ii/README.md

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+# [219.存在重复元素 II](https://leetcode-cn.com/problems/contains-duplicate-ii/description/)
+
+
+### 题目描述
+
+<div class="notranslate"><p>给定一个整数数组和一个整数&nbsp;<em>k</em>，判断数组中是否存在两个不同的索引<em>&nbsp;i</em>&nbsp;和<em>&nbsp;j</em>，使得&nbsp;<strong>nums [i] = nums [j]</strong>，并且 <em>i</em> 和 <em>j</em>&nbsp;的差的 <strong>绝对值</strong> 至多为 <em>k</em>。</p>
+
+<p>&nbsp;</p>
+
+<p><strong>示例&nbsp;1:</strong></p>
+
+<pre><strong>输入:</strong> nums = [1,2,3,1], k<em> </em>= 3
+<strong>输出:</strong> true</pre>
+
+<p><strong>示例 2:</strong></p>
+
+<pre><strong>输入: </strong>nums = [1,0,1,1], k<em> </em>=<em> </em>1
+<strong>输出:</strong> true</pre>
+
+<p><strong>示例 3:</strong></p>
+
+<pre><strong>输入: </strong>nums = [1,2,3,1,2,3], k<em> </em>=<em> </em>2
+<strong>输出:</strong> false</pre>
+</div>
+
+### 解题思路
+
+1. 利用hash表来实现
+
+### 代码实现
+
+<!-- tabs:start -->
+
+#### **Golang**
+```go
+func containsNearbyDuplicate(nums []int, k int) bool {
+	var numMap = make(map[int]int, 0)
+	for i, v := range nums {
+		if ii, ok := numMap[v]; ok && (i-ii) <= k {
+			return true
+		}
+		numMap[v] = i
+	}
+	return false
+}
+```
+
+
+<!-- tabs:end -->

solution/200-299/0219.contains-duplicate-ii/solution.go

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+package leetcode
+
+/*
+ * @lc app=leetcode.cn id=219 lang=golang
+ *
+ * [219] 存在重复元素 II
+ */
+
+// @lc code=start
+func containsNearbyDuplicate(nums []int, k int) bool {
+	var numMap = make(map[int]int, 0)
+	for i, v := range nums {
+		if ii, ok := numMap[v]; ok && (i-ii) <= k {
+			return true
+		}
+		numMap[v] = i
+	}
+	return false
+}
+
+// @lc code=end

solution/200-299/0219.contains-duplicate-ii/solution_test.go

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+package leetcode
+
+import (
+	"testing"
+)
+
+func TestPlusOne(t *testing.T) {
+	var nums []int
+	var ret bool
+	var k int
+
+	nums = []int{1, 2, 3, 1}
+	k = 3
+	ret = true
+	if ret != containsNearbyDuplicate(nums, k) {
+		t.Fatalf("case fails: %v\n", ret)
+	}
+
+	nums = []int{1, 0, 1, 1}
+	k = 1
+	ret = true
+	if ret != containsNearbyDuplicate(nums, k) {
+		t.Fatalf("case fails: %v\n", ret)
+	}
+
+	nums = []int{1, 2, 3, 1, 2, 3}
+	k = 2
+	ret = false
+	if ret != containsNearbyDuplicate(nums, k) {
+		t.Fatalf("case fails: %v\n", ret)
+	}
+}