1
樣例輸出
2
思路：埃拉托色尼篩選法求素數
AC代碼：
import java.math.BigInteger;import java.util.Scanner;public class Main {		static boolean[] a = new boolean[100010];		public static void main(String[] args) {				Scanner in = new Scanner(System.in);		int n = in.nextInt();		//打10倍的表應該可以了		doPRime(n*10);		int sum = 1;		int j = 2;		for (int i=1; i<=n;) {			if (!a[j]) {				sum = (sum * j) % 50000;				i++;			}			j++;		}		System.out.println(sum); 	}		public static void doPrime(int n) {		for (int i=2; i*i<=n; i++) {			if (!a[i]) {				for (int j=i*i; j<=n; j+=i) {					a[j] = true;				}			}		}	}}