23.05.03 Today’s Leetcode

2215. Find the Difference of Two Arrays (easy)

class Solution:
    def findDifference(self, nums1: List[int], nums2: List[int]) -> List[List[int]]:
        a, b = set(nums1), set(nums2)
        res = []
        temp = set()
        for num in nums1:
            if num not in b:
                temp.add(num)
        res.append(list(temp))

        temp = set()
        for num in nums2:
            if num not in a:
                temp.add(num)
        res.append(list(temp))
        return res

2216. Minimum Deletions to Make Array Beautiful (medium)

class Solution:
    def minDeletion(self, nums: List[int]) -> int:
        n = len(nums)
        i = res = 0
        while i + 1 < n:
            if nums[i] == nums[i + 1]:
                res += 1
                i -= 1 
            i += 2
        return res if (n - res) % 2 == 0 else res + 1
        

2217. Find Palindrome With Fixed Length (medium)

class Solution:
    def kthPalindrome(self, queries: List[int], intLength: int) -> List[int]:

        def get_palindrome(n, k):
            num = 10 ** ((n - 1) // 2)
            num += (k - 1)
            a = str(num)
            b = a[::-1]
            if n % 2 != 0:
                b = b[1:]
            p = a + b
            if len(p) != n:
                return -1
            return int(p)
        
        res = []
        for query in queries:
            res.append(get_palindrome(intLength, query))
        return res