LeetCode-Go/Algorithms/41.First-Missing-Positive

41. First Missing Positive

题目

Given an unsorted integer array, find the smallest missing positive integer.

Example 1:

Input: [1,2,0] Output: 3 Example 2:

Input: [3,4,-1,1] Output: 2 Example 3:

Input: [7,8,9,11,12] Output: 1 Note:

Your algorithm should run in O(n) time and uses constant extra space.