
Help!!!
Can someone explain the following questions from a mock java exam.
1.To what value must result be set for the loop to execute 2 times:
int num = 23;
int result = ?;
while((num>1)&& (result<32)) {
num = num/2;
result= result + 1
}
The answer that is on the answer sheet is 29, can someone explain
how?
2.The following code produces which sequence of numbers?
boolean t;
int a = 0;
int b = 1;
int c = 1;
for(int n = 0; a < 25; n++) {
t = false;
for (int j = a ; j < a + 4; j++) {
if (a%2==0) t = true;
if (t) system.out.println(j);
}
c = a;
a = b;
b = c+b;
}
can some explain how they got the sequence of numbers : 0,1,2,3,2,3,4,5,8,9,10,11
?
3.In the following problem what is printed?
int c = 0;
int d = 23,
do {
c+=3;
d=1;
}while(c<10 && d!=20);
system.out.println(c+d);
The answer on the sheet is 29, but I get 25?, can someone explain
how they
get 29?
4.Nothing to do with java but this is part of the mock paper.
For the BackusNaur Form (BNF) grammar which of the following is
an INVALID
string?
<string> ::=a<A>
<A> ::=b<A>a<B><C>
<B> ::=a<B><C>
<C> ::=b
The answer that they give is aaba, can anyone explain how they got
that answer?.
Thanks