# 2628. JSON Deep Equal

###### tags: `leetcode 30 days js challenge` `Medium`

[2628. JSON Deep Equal](https://leetcode.com/problems/json-deep-equal/)

### 題目描述

Given two objects `o1` and `o2`, check if they are **deeply equal**.

For two objects to be **deeply equal**, they must contain the same keys, and the associated values must also be **deeply equal**. Two objects are also considered **deeply equal** if they pass the `===` equality check.

You may assume both objects are the output of `JSON.parse`. In other words, they are valid JSON.

Please solve it without using lodash's `_.isEqual()` function.

### 範例

**Example 1:**

Input: o1 = {"x":1,"y":2}, o2 = {"x":1,"y":2}
Output: true
Explanation: The keys and values match exactly.

**Example 2:**

Input: o1 = {"y":2,"x":1}, o2 = {"x":1,"y":2}
Output: true
Explanation: Although the keys are in a different order, they still match exactly.

**Example 3:**

Input: o1 = {"x":null,"L":[1,2,3]}, o2 = {"x":null,"L":["1","2","3"]}
Output: false
Explanation: The array of numbers is different from the array of strings.

**Example 4:**

Input: o1 = true, o2 = false
Output: false
Explanation: true !== false

**Constraints**:

- 1 <= `JSON.stringify(o1).length` <= 10⁵
- 1 <= `JSON.stringify(o2).length` <= 10⁵
- `maxNestingDepth <= 1000`

### 解答

#### TypeScript

function areDeeplyEqual(o1: any, o2: any): boolean {
  if (o1 === o2) return true;

  if (o1 === null || o2 === null) return false;

  if (typeof o1 !== typeof o2) return false;

  if (Array.isArray(o1) !== Array.isArray(o2)) return false;

  if (typeof o1 === 'object') {
    const o1Keys = Object.keys(o1);
    const o2Keys = new Set(Object.keys(o2));

    if (o1Keys.length !== o2Keys.size) return false;

    for (const key of o1Keys) {
      if (!o2Keys.has(key)) return false;

      if (!areDeeplyEqual(o1[key], o2[key])) return false;
    }

    return true;
  }

  return false;
}

> [name=Sheep][time=Sun, May 21, 2023]

### Reference

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