随机数产生机制 解释器将代码加载到内存的处理

import time, random


def m(t=3000 * 20 * 1 * random.randint(0, 20)):
    print(t)
    print(time.time())
    time.sleep(1)


[m() for i in range(8)]

420000
1526986984.627107
420000
1526986985.6277814
420000
1526986986.6284676
420000
1526986987.6290512
420000
1526986988.6297226
420000
1526986989.6304398
420000
1526986990.6310155
420000
1526986991.6319053

每次运行程序，随机值确定

改变睡眠时间，仍然

import time, random


def m(t=3000 * 20 * 1 * random.randint(0, 20) * time.time()):
    print(t)
    print(time.time())
    time.sleep(10)


[m() for i in range(8)]

1007811503605215.2
1526987126.6745687
1007811503605215.2
1526987136.6750913
1007811503605215.2
1526987146.6759949
1007811503605215.2
1526987156.6767433
1007811503605215.2
1526987166.6768875

import time, random


def m(t=3000 * 20 * 1 * random.randint(0, 20)):
    print(t)
    print(time.time())
    time.sleep(1)


[m(3000 * 20 * 1 * random.randint(0, 20)) for i in range(8)]

1080000
1526987280.9112635
780000
1526987281.9114752
540000
1526987282.9115393
480000
1526987283.912519

解释器初始化 环境时，已经赋值

python  变量类型

import time, random


def m(t=3000 * 20 * 1, to_shuffle=True, to_shuffle_l=[0, 18]):
    if to_shuffle:
        t = t * random.randint(to_shuffle_l[0], to_shuffle_l[1])
    print(t)

    print(time.time())
    time.sleep(1)


[m() for i in range(8)]

package tts.producing;

import java.util.Random;

public class MyTest {

    public int randomPositiveInt() {
        int i = new Random().nextInt();
        return Math.abs(i);
    }

    public String randomPositiveIntWithTm() {
        int i = this.randomPositiveInt();
        long tmMillis = System.currentTimeMillis();
        String r = String.valueOf(i) + "_" + String.valueOf(tmMillis);
        return r;
    }

    public static void main(String[] args) {
        MyTest t = new MyTest();
        String d = t.randomPositiveIntWithTm();
        System.out.println(d);


    }
}