LeetCode-in-All
300. Longest Increasing Subsequence
Medium
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
Constraints:
1 <= nums.length <= 2500-104 <= nums[i] <= 104
Follow up: Can you come up with an algorithm that runs in O(n log(n)) time complexity?
Solution
/**
* @param {number[]} nums
* @return {number}
*/
var lengthOfLIS = function (nums) {
const dp = []
for (let num of nums) {
let start = 0
let end = dp.length
while (start < end) {
const mid = Math.floor((start + end) / 2)
if (dp[mid] < num) {
start = mid + 1
} else {
end = mid
}
}
dp[start] = num
}
return dp.length
};
export { lengthOfLIS }