题目描述
A Sphenic Number is a positive integer N which is product of exactly three distinct primes. The first few sphenic numbers are 30, 42, 66, 70, 78, 102, 105, 110, 114, …
Given a number N, your task is to find whether it is a Sphenic Number or not.
Example 1:
Input: N = 30
Output: 1
Explanation: 30 = 2 * 3 * 5 so N is
product of 3 distinct prime numbers.
Example 2:
Input: N = 60
Output: 0
Explanation: 60 = 2 * 2 * 3 * 5 so N is
product of 4 prime numbers.
Your Task:
You don't need to read or print anyhting. Your task is to complete the function isSphenicNo() which takes N as input parameter and returns 1 if N is Sphenic Number otherwise returns 0.
Expected Time Complexity: O(N* log(N))
Expected Space Complexity: O(N)
Constraints:
1 <= N <= 1000
输入格式
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输出格式
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