public class Solution {
public IList<int> FindDisappearedNumbers(int[] nums) {
Dictionary<int, int> dic = new Dictionary<int, int>();
for (int i = ; i <= nums.Length; i++)
{
dic.Add(i, );
} for (int i = ; i < nums.Length; i++)
{
dic[nums[i]]++;
} var list = new List<int>();
for (int i = ; i <= nums.Length; i++)
{
if (dic[i] == )
{
list.Add(i);
}
} return list;
}
}
https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/#/description