题目描述
A prime number is Super Prime if it is a sum of two primes. Find all the Super Primes upto N
Example 1:
Input:
N = 5
Output: 1
Explanation: 5 = 2 + 3, 5 is the
only super prime
Example 2:
Input:
N = 10
Output: 2
Explanation: 5 and 7 are super primes
Your Task:
You don't need to read input or print anything. Your task is to complete the function superPrimes() which takes the N as input and returns the count of super primes.
Expected Time Complexity: O(Nlog(logN))
Expected Auxiliary Space: O(N)
Constraints:
1 ≤ N ≤ 10^{5}
输入格式
见题面
输出格式
见题面
样例输入
N = 5
样例输出
1