Problem F: 筛质数
Memory Limit:128 MB
Time Limit:1.000 S
Judge Style:Text Compare
Creator:
Submit:142
Solved:51
Description
给定一个正整数 n ,请你求出 1∼n 中质数的个数。(1<=n<=10^6)
Input
输入一个n
Output
输出n以内的质数个数
Sample Input Copy
8
Sample Output Copy
4