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412. Fizz Buzz

If you are given an integer n, find the Fizz Buzz representation of each integer from 1 to n, and return the result with an array of strings (subscript starting from 1) :

  • Answer [I] == “FizzBuzz” if I is a multiple of 3 and 5.
  • Answer [I] == “Fizz” if I is a multiple of 3.
  • Answer [I] == “Buzz” if I is a multiple of 5.
  • Answer [I] == I If none of the above conditions are met.

 

Example 1: Input: n = 3 Output: ["1","2","Fizz"] Example 2: Input: n = 5 Output: ["1","2","Fizz","4","Buzz"] Example 3: Input: n = 15 Output: ["1","2","Fizz","4","Buzz","Fizz","7","8","Fizz","Buzz","11","Fizz","13","14","FizzBuzz"]Copy the code

Their thinking

Answer [I] answer[I] answer[I] answer[I] answer[I] answer[I] answer[I] answer[I] Answer [I] contains both “Fizz” and” Fuzz”, and “Fizz” precedes” Buzz”.

Iterate over [1…n] to see if I satisfies the requirement that it be a multiple of 3 and 5 at the same time. Output “FizzBuzz”. If I is a multiple of 3, print “Fizz”. If I is a multiple of 5, print “Buzz”. Otherwise print I

code

class Solution {
    public List<String> fizzBuzz(int n) {

        List<String> res=new ArrayList<>();
        
        for(int i=1; i<=n; i++) {if(i%3= =0&&i%5= =0)
            {
                res.add("FizzBuzz");
            }else if(i%3= =0){
                res.add("Fizz");
            }else if(i%5= =0)
            {
                res.add("Buzz");
            }else res.add(""+i);
            
        }
        returnres; }}Copy the code
    public List<String> fizzBuzz(int n) {

        List<String> res=new ArrayList<>();
        
        for(int i=1; i<=n; i++) { StringBuilder sb=new StringBuilder();
           if(i%3= =0){
                sb.append("Fizz");
            }
            if(i%5= =0)
            {
                 sb.append("Buzz");
            }
            if(sb.length()==0)
             sb.append(""+i);
             res.add(sb.toString());
        }
        return res;
    }
Copy the code

  • Time complexity: O(n). Each integer from 1 to n needs to be traversed. For each integer I, the time complexity of generating answer[I] is O(1).

  • Space complexity: O(1). Note that the returned value does not count space complexity