有效的字母易位词

题目描述：

代码：

class Solution(object):
    def isAnagram(self, s, t):
        record = [0] * 26
        for i in range(len(s)):
            record[ord(s[i])-ord('a')] += 1
        for i in range(len(t)):
            record[ord(t[i])-ord('a')] -= 1
        for i in range(26):
            if record[i] != 0:
                return False
        return True

两个数组的交集

题目描述：

代码：

class Solution(object):
    def intersection(self, nums1, nums2):
        return list(set(nums1)&set(nums2))

快乐数

题目描述：

代码：

class Solution(object):
    def isHappy(self, n):
        def calculateHappy(n):
            sum = 0
            while n:
                s = (n % 10) ** 2
                n = n // 10
                sum += s
            return sum
    
        record = set()
    
        while True:
            n = calculateHappy(n)
            if n == 1:
                return True
            elif n in record:
                return False
            else:
                record.add(n)

题目描述：

代码：

class Solution(object):
    def twoSum(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: List[int]
        """
        records = {}
        for i, n in enumerate(nums):
            if target - n in records:
                return [records[target - n], i]
            else:
                records[n] = i