algorithm notes: leetcode#412 fizz buzz

Problem

Write a program that outputs the string representation of numbers from 1 to n.

But for multiples of three it should output “Fizz” instead of the number and for the multiples of five output “Buzz”. For numbers which are multiples of both three and five output “FizzBuzz”.

Example:

n = 15,

Return:
[
“1”,
“2”,
“Fizz”,
“4”,
“Buzz”,
“Fizz”,
“7”,
“8”,
“Fizz”,
“Buzz”,
“11”,
“Fizz”,
“13”,
“14”,
“FizzBuzz”
]

Solution

Analysis

Iterate numbers from 1 to n. If a number is multiples of 15, output “FizzBuzz”. If it is multiples of 3, output “Fizz”. If it is multiples of 5, output “Buzz”. Otherwise, convert it to string and output.

Python implementation

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class :
    def fizzBuzz(self, n):
        """
        :type n: int
        :rtype: List[str]
        """
        def func(num):
            if num % 15 == 0:
                return "FizzBuzz"
            if num % 3 == 0:
                return "Fizz"
            if num % 5 == 0:
                return "Buzz"
            return str(num)
        
        return [func(num) for num in range(1, n+1)]

Java implementation

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class  {
    public List<String> fizzBuzz(int n) {
        List<String> ans = new ArrayList<>();
        
        for(int i = 1; i <= n; i++){
            if(i % 15 == 0){ 
                ans.add("FizzBuzz");
            }else if(i % 3 == 0){
                ans.add("Fizz");
            }else if(i % 5 == 0){
                ans.add("Buzz");
            }else {
                ans.add(Integer.toString(i));
            }
        }
        
        return ans;
    }
}

Time complexity

O(N). Iterate numbers from 1 to n.

Space complexity

O(1).

Links

412. Fizz Buzz
(中文版) 算法笔记: 力扣#412 Fizz Buzz