apcsa-String

Consider s1 and s2 are String:

       s1 = "aardvark";

  s2 = s1.substring(4);

What does s2 get?

• dvar

• vark

• ark

• dvark

Assume the following declaration exists:

String qqq = "Haleakala";

 What will be output after the statement executed

    System.out.println(qqq.substring(5,9));

Assume the following declaration exists:

   

    String qqq = "Haleakala";

    int  index= qqq.indexOf("leak");

What is the value of index?

Assume the following declaration:

String kkk=“princess”;

String yyy=“princesS”;

 int   x=kkk.compareTo(yyy);

What is the value of x then?

(tip:返回ascII码差值，小写a是97， 大写A是65)

Suppose:

 String name=“Mississippi”;

 int length=name.length();

What is the value of length?

What is the index value of character “d”  in string “Amanda”?

Suppose that strA=”TOMATO”, strB=”tomato”, and strC=”tom”. Given that “A” comes before “a” in dictionary order, which is true?

• strA.compareTo(strB)<0  && strB.compareTo(strC)<0

• strB.compareTo(strA)<0 || strC.compareTo(strA)<0

• strC.compareTo(strA)<0  && strA.compareTo(strB)<0

• !(strA.equals(strB)) && strC.compareTo(strB)<0

Answer explanation

D。strB比strC大三，因为多三个字母，如果strB是 tomato22， 那么他比strC大5， 因为多5个字母。反之是-3；

Assume:

String str = "Mississippi is a state and it is a river.";

System.out.println(str.indexOf("is"));

What is the output?

String s1 = "Hi There";

String s2 = s1;

String s3 = s2;

String s4 = s1;

s2 = s2.toLowerCase();

s3 = s3.toUpperCase();

s4 = null;

what is the value of s1 after the code executes?

• null

• hi there

• HI THERE

• Hi There

String s1 = "Hi There";

String s2 = “ Hello”;

String s3 = s1+s2;

what is the value of s3 after the code executes?

• null

• hi there

• Hi There

• Hello

• Hi There Hello