J. Macha

Greenhorn

Posts: 12

posted 17 years ago

The following is a question from the pgjc - mock exam that i think has an incorrect answer.

1. Which of statements are true concerning the effect of the >> and >>> operators?

a) for non-negative values of the left operand, the >> and >>> operators will have the same effect.

b) the result of (-1 >> 1) is 0

c) the result of (-1 >>> 1) is -1

d) the value returned by >>> will never be negative as long as the value of the right operand is equal to or greater than 1

e) when using the >> operator, the left most bit of the bit representation of the resulting value will always be the same bit value as the leftmost bit of the bit representation of the left operand.

the mock exam has the answer as A,D,E

i think that the correct answer is A, E

D is incorrect for example (-10 >>> 32) is still -10

1. Which of statements are true concerning the effect of the >> and >>> operators?

a) for non-negative values of the left operand, the >> and >>> operators will have the same effect.

b) the result of (-1 >> 1) is 0

c) the result of (-1 >>> 1) is -1

d) the value returned by >>> will never be negative as long as the value of the right operand is equal to or greater than 1

e) when using the >> operator, the left most bit of the bit representation of the resulting value will always be the same bit value as the leftmost bit of the bit representation of the left operand.

the mock exam has the answer as A,D,E

i think that the correct answer is A, E

D is incorrect for example (-10 >>> 32) is still -10

J. Macha

Greenhorn

Posts: 12

posted 17 years ago

The pgjc exam also has the following question.

Which are valid identifiers.

a) class

b) $value$

c) zer@

d) angstrom

e) 2much

it has the answer as being A,B,D

but class is a reserved word so it can not be used as an identifier

Which are valid identifiers.

a) class

b) $value$

c) zer@

d) angstrom

e) 2much

it has the answer as being A,B,D

but class is a reserved word so it can not be used as an identifier

Erin Waite

Greenhorn

Posts: 6

posted 17 years ago

Hi Macha,

The answer d of your first question in my book is

d) The value returned by >>> will never be negative as long as the value of the right operand is not divisible by 32.

So the answer d is correct.

The answer a of your second question in my book is

a) _class

So the answer a is also correct.

Thanks,

Erin

The answer d of your first question in my book is

d) The value returned by >>> will never be negative as long as the value of the right operand is not divisible by 32.

So the answer d is correct.

The answer a of your second question in my book is

a) _class

So the answer a is also correct.

Thanks,

Erin

J. Macha

Greenhorn

Posts: 12

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