Fizz Buzz

题目

写一个程序，输出从1到n数字的字符串表示。

1. 如果n是3的倍数，输出”Fizz”；
2. 如果n是5的倍数，输出”Buzz”;
3. 如果n同时是3和5的倍数，输出”FizzBuzz”。

思路

一、暴力法

class Solution:
    def fizzBuzz(self, n: int) -> List[str]:
        ans = []
        for i in range(1, n+1):
            if i % 3 == 0:
                if i % 5 == 0:
                    ans.append('FizzBuzz')
                else:
                    ans.append('Fizz')
            elif i % 5 == 0:
                ans.append('Buzz')
            else:
                ans.append(str(i))
        return ans

填一下官方代码，写得确实优雅。

class Solution:
    def fizzBuzz(self, n):
        """
        :type n: int
        :rtype: List[str]
        """
        # ans list
        ans = []
        for num in range(1,n+1):
            divisible_by_3 = (num % 3 == 0)
            divisible_by_5 = (num % 5 == 0)
            if divisible_by_3 and divisible_by_5:
                # Divides by both 3 and 5, add FizzBuzz
                ans.append("FizzBuzz")
            elif divisible_by_3:
                # Divides by 3, add Fizz
                ans.append("Fizz")
            elif divisible_by_5:
                # Divides by 5, add Buzz
                ans.append("Buzz")
            else:
                # Not divisible by 3 or 5, add the number
                ans.append(str(num))
        return ans

二、字符串连接

class Solution:
    def fizzBuzz(self, n):
        """
        :type n: int
        :rtype: List[str]
        """
        # ans list
        ans = []
        for num in range(1,n+1):
            divisible_by_3 = (num % 3 == 0)
            divisible_by_5 = (num % 5 == 0)
            num_ans_str = ""
            if divisible_by_3:
                # Divides by 3
                num_ans_str += "Fizz"
            if divisible_by_5:
                # Divides by 5
                num_ans_str += "Buzz"
            if not num_ans_str:
                # Not divisible by 3 or 5
                num_ans_str = str(num)
            # Append the current answer str to the ans list
            ans.append(num_ans_str)  
        return ans

三、更优雅且具有扩展性的实现：散列表

class Solution:
    def fizzBuzz(self, n):
        """
        :type n: int
        :rtype: List[str]
        """
        # ans list
        ans = []
        # Dictionary to store all fizzbuzz mappings
        fizz_buzz_dict = {3 : "Fizz", 5 : "Buzz"}
        for num in range(1,n+1):
            num_ans_str = ""
            for key in fizz_buzz_dict.keys():
                # If the num is divisible by key,
                # then add the corresponding string mapping to current num_ans_str
                if num % key == 0:
                    num_ans_str += fizz_buzz_dict[key]
            if not num_ans_str:
                num_ans_str = str(num)
            # Append the current answer str to the ans list
            ans.append(num_ans_str)  
        return ans