java小程序之随机产生一个从0-100之间的整数，判断是否是质数

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
package learnjava;
import java.util.Random;





public class Demo9 {
	public static void main(String []args) {
		int num;
		Random random = new Random();
		num = random.nextInt(100);
		System.out.println("随机产生的数为" + num);
		System.out.println(isPrime(num));
		
	}
	public static boolean isPrime (int num) {
		if(num < 2) {
			return false;
			
		}
		if(num == 2) {
			return true;
			
		}
		if(num % 2 == 0) {
			return false;
			
		}
		for(int i = 3; i <= Math.sqrt(num); i++) {
			if(num % i == 0) {
				return false;
				
			}
		}
		return true;
		
	}
}
package learnjava;
import java.util.Random;





public class Demo9 {
	public static void main(String []args) {
		int num;
		Random random = new Random();
		num = random.nextInt(100);
		System.out.println("随机产生的数为" + num);
		System.out.println(isPrime(num));
		
	}
	public static boolean isPrime (int num) {
		if(num < 2) {
			return false;
			
		}
		if(num == 2) {
			return true;
			
		}
		if(num % 2 == 0) {
			return false;
			
		}
		for(int i = 3; i <= Math.sqrt(num); i++) {
			if(num % i == 0) {
				return false;
				
			}
		}
		return true;
		
	}
}