add eslint support

.eslintrc.json

@@ -0,0 +1,25 @@
+{
+    "env": {
+        "browser": true,
+        "es6": true
+    },
+    "extends": "eslint:recommended",
+    "rules": {
+        "indent": [
+            "error",
+            4
+        ],
+        "linebreak-style": [
+            "error",
+            "unix"
+        ],
+        "quotes": [
+            "error",
+            "single"
+        ],
+        "semi": [
+            "error",
+            "never"
+        ]
+    }
+}

.gitignore

@@ -0,0 +1,2 @@
+.vscode
+node_modules

.vscode/c_cpp_properties.json

@@ -1,77 +0,0 @@
-{
-    "configurations": [
-        {
-            "name": "Mac",
-            "includePath": [
-                "/usr/include",
-                "/usr/local/include",
-                "${workspaceRoot}"
-            ],
-            "defines": [],
-            "intelliSenseMode": "clang-x64",
-            "browse": {
-                "path": [
-                    "/usr/include",
-                    "/usr/local/include",
-                    "${workspaceRoot}"
-                ],
-                "limitSymbolsToIncludedHeaders": true,
-                "databaseFilename": ""
-            },
-            "macFrameworkPath": [
-                "/System/Library/Frameworks",
-                "/Library/Frameworks"
-            ]
-        },
-        {
-            "name": "Linux",
-            "includePath": [
-                "/usr/include",
-                "/usr/local/include",
-                "${workspaceRoot}"
-            ],
-            "defines": [],
-            "intelliSenseMode": "clang-x64",
-            "browse": {
-                "path": [
-                    "/usr/include",
-                    "/usr/local/include",
-                    "${workspaceRoot}"
-                ],
-                "limitSymbolsToIncludedHeaders": true,
-                "databaseFilename": ""
-            }
-        },
-        {
-            "name": "Win32",
-            "includePath": [
-                "C:/Program Files (x86)/Microsoft Visual Studio/2017/Enterprise/VC/Tools/MSVC/14.11.25503/include/*",
-                "C:/Program Files (x86)/Microsoft Visual Studio/2017/Enterprise/VC/Tools/MSVC/14.11.25503/atlmfc/include/*",
-                "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/um",
-                "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/ucrt",
-                "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/shared",
-                "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/winrt",
-                "${workspaceRoot}"
-            ],
-            "defines": [
-                "_DEBUG",
-                "UNICODE"
-            ],
-            "intelliSenseMode": "msvc-x64",
-            "browse": {
-                "path": [
-                    "C:/Program Files (x86)/Microsoft Visual Studio/2017/Enterprise/VC/Tools/MSVC/14.11.25503/include/*",
-                    "C:/Program Files (x86)/Microsoft Visual Studio/2017/Enterprise/VC/Tools/MSVC/14.11.25503/atlmfc/include/*",
-                    "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/um",
-                    "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/ucrt",
-                    "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/shared",
-                    "C:/Program Files (x86)/Windows Kits/10/Include/10.0.15063.0/winrt",
-                    "${workspaceRoot}"
-                ],
-                "limitSymbolsToIncludedHeaders": true,
-                "databaseFilename": ""
-            }
-        }
-    ],
-    "version": 3
-}

.vscode/launch.json

@@ -1,22 +0,0 @@
-{
-    // 使用 IntelliSense 了解相关属性。 
-    // 悬停以查看现有属性的描述。
-    // 欲了解更多信息，请访问: https://go.microsoft.com/fwlink/?linkid=830387
-    "version": "0.2.0",
-    "configurations": [
-        
-        {
-            "name": "Launch",
-            "type": "go",
-            "request": "launch",
-            "mode": "debug",
-            "remotePath": "",
-            "port": 2345,
-            "host": "127.0.0.1",
-            "program": "${fileDirname}",
-            "env": {},
-            "args": [],
-            "showLog": true
-        }
-    ]
-}

easy/141.js

@@ -1,3 +1,5 @@
+'use strict'
+
 /**
  * Definition for singly-linked list.
  * function ListNode(val) {

easy/160.js

@@ -1,3 +1,5 @@
+'use strict'
+
 /**
  * Definition for singly-linked list.
  * function ListNode(val) {

easy/190.js

@@ -1,3 +1,5 @@
+'use strict'
+
 /**
  * @param {number} n - a positive integer
  * @return {number} - a positive integer

easy/191.js

@@ -1,3 +1,5 @@
+'use strict'
+
 /**
  * @param {number} n - a positive integer
  * @return {number}