Package g0001_0100.s0041_first_missing_positive

Class Solution

java.lang.Object
g0001_0100.s0041_first_missing_positive.Solution
public class Solution extends Object
41 - First Missing Positive.

Hard

Given an unsorted integer array nums, return the smallest missing positive integer.

You must implement an algorithm that runs in O(n) time and uses constant extra space.

Example 1:

Input: nums = [1,2,0]

Output: 3

Example 2:

Input: nums = [3,4,-1,1]

Output: 2

Example 3:

Input: nums = [7,8,9,11,12]

Output: 1

Constraints:

  • 1 <= nums.length <= 5 * 105
  • -231 <= nums[i] <= 231 - 1

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • firstMissingPositive

      public int firstMissingPositive(int[] nums)