#41

First Missing Positive

master · 1640 · lc hard +32 · verified · 42.5% accepted · 18,302 likes · top 24%

Description

Return the smallest positive integer absent from unsorted integer array nums. The algorithm must run in O(n) time using O(1) auxiliary space.

Example 1:

Input: nums = [1,2,0]

Output: 3

Explanation: The numbers in the range [1,2] are all in the array.

Example 2:

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

Output: 2

Explanation: 1 is in the array but 2 is missing.

Example 3:

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

Output: 1

Explanation: The smallest positive integer 1 is missing.

Code

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class Solution:
    def firstMissingPositive(self, nums: List[int]) -> int:

class Solution:
    def firstMissingPositive(self, nums: List[int]) -> int: