# Leetcode 300. Longest Increasing Subsequence

medium — apple interview question

# Problem

Given an integer array `nums`

, return the length of the longest strictly increasing subsequence.

A **subsequence** is a sequence that can be derived from an array by deleting some or no elements without changing the order of the remaining elements. For example, `[3,6,2,7]`

is a subsequence of the array `[0,3,1,6,2,2,7]`

.

**Example 1:**

**Input:** nums = [10,9,2,5,3,7,101,18]

**Output:** 4

**Explanation:** The longest increasing subsequence is [2,3,7,101], therefore the length is 4.

**Example 2:**

**Input:** nums = [0,1,0,3,2,3]

**Output:** 4

**Example 3:**

**Input:** nums = [7,7,7,7,7,7,7]

**Output:** 1

# Solutions

- Brute Force

`choose`

or `not choose`

. This will make 2^n algorithm. Pretty bad.

2. Dynamic programming