接口 Map的主要实现类有、Hashtable和 。
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密码要求必须由数字或字母组成,长度是 6-12,请写出密码的正则表达式: 。手机号以 1开始,第 2位为 358中任意一位其它全部是数字,长度是 11位,写出手机号的正则表达式: 。
Given:11. int i=(int)Math.random();What is the value of i after line 11?Correct Answers:
A. 0
B. 1
Compilation fails.
D. any positive integer between 0 and Integer.MAX_VALUE
E. any integer between Integer.MIN_VALUE and Integer.MAX_VALUE
Given:String s=1+9+"Hello";System.out.println(s);What is the result?Correct Answers:
A. 19Hello
B. 10Hello
Compilation fails.
D. An exception is thrown at runtime.
Given:String a = "ABCD";String b = a.toLowerCase();b.replace('a', 'd');b.replace('b', 'c');System.out.println(b);What is the result?Correct Answers:
A. abcd
B. ABCD
C. dccd
D. dcba
E. Compilation fails.
F. An exception is thrown at runtime