题解 | 判断素数个数

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int start = scanner.nextInt();
        int end = scanner.nextInt();
        method(start,end);
    }

    public static void method(int start, int end) {
        int count=0;
        if(start>end)
        {
            int box=start;
            start=end;
            end=box;
        }
        if(start<2&&end<2)
        count=0;
        else
        {
            if(start<2)
            start=2;
            for(int i=start;i<=end;i++)
            {
                int f=1;
                for(int j=2;j<i;j++)
                {
                    if(i%j==0)
                    {
                        f=0;
                        break;
                    }
                }
                if(f==1)
                count++;
            
            }
        }

        System.out.println(start+"到"+end+"之间有"+count+"个大于2的素数");
    }
}