题目描述
A palindromic prime (sometimes called a palprime) is a prime number that is also a palindromic number.Given a number n, output the count of numbers less than or equal to n which are palindromic prime.
Example 1:
Input:
n = 3
Output:
2
Explanation:
There are 2 palprimes less than or
equal to 3. They are 2, and 3.
Example 2:
Input:
n = 12
Output:
5
Explanation:
There are 5 palprimes less than or
equal to 12. They are 2, 3, 5, 7, and 11.
Your Task:
You don't need to read input or print anything. Your task is to complete the function palPrimes() which takes an Integer n as input and returns the number of palprimes less than or equal to n.
Expected Time Complexity: O(n*(log(log(n))))
Expected Auxiliary Space: O(n)
Constraints:
1 <= n <= 10^{6}
输入格式
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输出格式
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