环球新资讯：Leetcode 2549. Count Distinct Numbers on Board

You are given a positive integer n, that is initially placed on a board. Every day, for 109days, you perform the following procedure:

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For each number xpresent on the board, find all numbers 1 <= i <= nsuch that x % i == 1.

Then, place those numbers on the board.

Return the number of distinct integers present on the board after 109days have elapsed.

Note:

Once a number is placed on the board, it will remain on it until the end.

%stands for the modulo operation. For example, 14 % 3is 2.

Example 1:

Input: n = 5Output: 4Explanation: Initially, 5 is present on the board. The next day, 2 and 4 will be added since 5 % 2 == 1 and 5 % 4 == 1. After that day, 3 will be added to the board because 4 % 3 == 1. At the end of a billion days, the distinct numbers on the board will be 2, 3, 4, and 5.

Example 2:

Input: n = 3Output: 2Explanation: Since 3 % 2 == 1, 2 will be added to the board. After a billion days, the only two distinct numbers on the board are 2 and 3.

Runtime: 0 ms, faster than 100.00% of Java online submissions for Count Distinct Numbers on Board.

Memory Usage: 38.9 MB, less than 85.71% of Java online submissions for Count Distinct Numbers on Board.

关键词： DAYS Java DISTINCT INITIALLY