Leetcode 829. Consecutive Numbers Sum

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Given a positive integer N, how many ways can we write it as a sum of consecutive positive integers?

Example 1:

Input: 5
Output: 2
Explanation: 5 = 5 = 2 + 3

Example 2:

Input: 9
Output: 3
Explanation: 9 = 9 = 4 + 5 = 2 + 3 + 4

Example 3:

Input: 15
Output: 4
Explanation: 15 = 15 = 8 + 7 = 4 + 5 + 6 = 1 + 2 + 3 + 4 + 5

Note: 1 <= N <= 10 ^ 9.

    public int consecutiveNumbersSum(int N) {
        int count = 0;
        int n = 1;
        while (true) {
            int fenZi = 2*N - n*(n-1);
            if (fenZi <= 0) {
                break;
            }
            if (fenZi % (2*n) == 0) {
                count ++;
            }
            n++;
        }
        return count;
    }

 https://leetcode.com/problems/consecutive-numbers-sum/