Class Solution


  • public class Solution
    extends Object
    442 - Find All Duplicates in an Array.

    Medium

    Given an integer array nums of length n where all the integers of nums are in the range [1, n] and each integer appears once or twice , return an array of all the integers that appears twice.

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

    Example 1:

    Input: nums = [4,3,2,7,8,2,3,1]

    Output: [2,3]

    Example 2:

    Input: nums = [1,1,2]

    Output: [1]

    Example 3:

    Input: nums = [1]

    Output: []

    Constraints:

    • n == nums.length
    • 1 <= n <= 105
    • 1 <= nums[i] <= n
    • Each element in nums appears once or twice.
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • findDuplicates

        public List<Integer> findDuplicates​(int[] nums)