Check if Array is Good.py

'''
You are given an integer array nums. We consider an array good if it is a permutation of an array base[n].

base[n] = [1, 2, ..., n - 1, n, n] (in other words, it is an array of length n + 1 which contains 1 to n - 1 exactly once, plus two occurrences of n). For example, base[1] = [1, 1] and base[3] = [1, 2, 3, 3].

Return true if the given array is good, otherwise return false.

Note: A permutation of integers represents an arrangement of these numbers.
'''


class Solution:
    def isGood(self, nums: List[int]) -> bool:
        
        n =max(nums)

        basen = [i for i in range(1,n)]
        basen.append(n)
        basen.append(n)

        s1 = Counter(nums)
        s2 = Counter(basen)
        if len(basen)!= len(nums):
            return False
        for k,v in s1.items():
            if s1[k] != s2[k]:
                return False
        return True
-------------------------------------------------------------------
class Solution:
    def isGood(self, nums: List[int]) -> bool:
        

        base = len(nums)-1
        hashmap = defaultdict(int)
        for i in nums:
            if i > base:
                return False
            hashmap[i]+=1
        
            if i!=base and hashmap[i]>1:
                return False

        if hashmap[base]>2:
            return False
        return True