add: 最高频率的IP

README.md

@@ -303,6 +303,10 @@ LeetCode 与 LintCode 解题记录。此为个人练习仓库，代码中对重
   - LeetCode 152. 乘积最大子数组 <https://leetcode-cn.com/problems/maximum-product-subarray/>
   - LintCode 191. 乘积最大子序列 <https://www.lintcode.com/problem/maximum-product-subarray/description>
 
+- [最高频率的IP](src/array/highest-frequency-ip.js)
+
+  - LintCode 1613. 最高频率的IP <https://www.lintcode.com/problem/highest-frequency-ip/description>
+
 ## 栈
 
 - [最大矩阵](src/stack/maximal-rectangle.js)

src/array/highest-frequency-ip.js

@@ -0,0 +1,19 @@
+/**
+ * @param ipLines: ip  address
+ * @return: return highestFrequency ip address
+ */
+export const highestFrequency = function (ipLines) {
+  const map = new Map()
+  let max = 0
+  let maxN = ipLines[0]
+  ipLines.forEach(n => {
+    const temp = (map.get(n) || 0) + 1
+    map.set(n, temp)
+    if (temp > max) {
+      maxN = n
+      max = temp
+    }
+  })
+
+  return maxN
+}

test/array/highest-frequency-ip.test.js

@@ -0,0 +1,6 @@
+import { highestFrequency } from '../../src/array/highest-frequency-ip'
+
+test('最高频率的IP', () => {
+  expect(highestFrequency(['192.168.1.1', '192.118.2.1', '192.168.1.1'])).toEqual('192.168.1.1')
+  expect(highestFrequency(['192.168.1.1', '192.118.2.1', '192.168.1.1', '192.118.2.1', '192.118.2.1'])).toEqual('192.118.2.1')
+})