标签:traints def span out inpu add ons sort 注意
Given two positive integers n
and k
.
A factor of an integer n
is defined as an integer i
where n % i == 0
.
Consider a list of all factors of n
sorted in ascending order, return the kth
factor in this list or return -1 if n
has less than k
factors.
Example 1:
Input: n = 12, k = 3 Output: 3 Explanation: Factors list is [1, 2, 3, 4, 6, 12], the 3rd factor is 3.
Example 2:
Input: n = 7, k = 2 Output: 7 Explanation: Factors list is [1, 7], the 2nd factor is 7.
Example 3:
Input: n = 4, k = 4 Output: -1 Explanation: Factors list is [1, 2, 4], there is only 3 factors. We should return -1.
Example 4:
Input: n = 1, k = 1 Output: 1 Explanation: Factors list is [1], the 1st factor is 1.
Example 5:
Input: n = 1000, k = 3 Output: 4 Explanation: Factors list is [1, 2, 4, 5, 8, 10, 20, 25, 40, 50, 100, 125, 200, 250, 500, 1000].
Constraints:
1 <= k <= n <= 1000
class Solution { public int kthFactor(int n, int k) { int res = 0; List<Integer> fac = new ArrayList(); for(int i = 1; i <= n; i++){ if(n % i == 0) fac.add(i); } return k > fac.size() ? -1 : fac.get(k-1); } }
注意k的范围
标签:traints def span out inpu add ons sort 注意
原文地址:https://www.cnblogs.com/wentiliangkaihua/p/13205990.html