Give you two positive integers n and k .
If the positive integer is i satisfied n % i == 0 , then we say that the positive integer i is n a factor of the integer .
Consider n all factors of integers and arrange them in ascending order . Please return the k first factor. If n the number of factors is less than k , please return -1 .
Example 1:
Input: n = 12, k = 3 Output: 3 Explanation: The factor list includes [1, 2, 3, 4, 6, 12], and the third factor is 3.
Example 2:
Input: n = 7, k = 2 Output: 7 Explanation: The factor list includes [1, 7], and the second factor is 7.
Example 3:
Input: n = 4, k = 4 Output: -1 Explanation: The factor list includes [1, 2, 4] and there are only 3 factors, so we should return -1.
Example 4:
Input: n = 1, k = 1 Output: 1 Explanation: The factor list includes [1], and the first factor is 1.
Example 5:
Input: n = 1000, k = 3 Output: 4 Explanation: The factor list includes [1, 2, 4, 5, 8, 10, 20, 25, 40, 50, 100, 125, 200, 250, 500, 1000] .
prompt:
1 <= k <= n <= 1000
package Solution1492;
class Solution {
public int kthFactor(int n, int k) {
int count = 0;
for (int i = 1; i <= n; i++) {
if (n % i == 0) {
count++;
if (count == k) {
return i;
}
}
}
return -1;
}
public static void main(String[] args) {
Solution sol = new Solution();
int n = 7, k = 2;
System.out.println(sol.kthFactor(n, k));
}
}