Introduction to Java
Unit 2.
Exercises
Note: Curly brackets {} are optional if there is only
one statement associated with the if (or else)
statement.
Scanner get = new Scanner(System.in);
System.out.print( "Enter a number: " );
int x = get.nextInt();
1. If the user enters 82, what is displayed?
if ( x < 7 )
System.out.println( "Good" );
else
System.out.println( "Bad" );
Bad
Ok
2. If the user enters 2, what is displayed?
Good
Ok
3. If the user enters 10, what is displayed?
AA
BB
CC
4. If the user enters 12, what is displayed?
AA
CC
if ( x > 0 )
System.out.println( "Ok" );
Scanner get = new Scanner(System.in);
System.out.print( "Enter a number: " );
int x = get.nextInt();
System.out.println( "AA" );
if ( x <= 11 ) {
System.out.println( "BB" );
}
System.out.println( "CC" );
5. If the user enters 10, what is displayed?
30
Scanner get = new Scanner(System.in);
System.out.print( "Enter a number: " );
int x = get.nextInt();
6. If the user enters 4, what is displayed?
if ( x != 10 )
x = x + 5;
29
7. If the user enters 2, what is displayed?
37
if ( x > 7 )
x = x + 20;
else
x = x + 30;
System.out.println( x );
8. If x has an initial value of 33, what is its
final value?
39
8. If x has an initial value of 62, what is its final
value?
// x is declared and assigned a value
if ( x > 30 && x <= 50 ) {
x = x + 10;
}
x = x - 4;
if ( x < 40 && x > 60 )
page 1
62
x = x + 2;
page 2
10. If x has a value of -5 and y has a value of
63, what is displayed?
H
K
// x and y are declared and initialized
11. If x has a value of 47 and y has a value of 47,
what is displayed?
if ( x < 100 || x > 40 )
System.out.println( "H" );
G
if ( y < 10 || y > 50 )
System.out.println( "K" );
if ( x > 30 || y >= 60 )
System.out.println( "G" );
H
12. Select the TRUE statement.
a)
H is never printed.
b)
H is always printed.
c)
H is only printed sometimes.
13. If y has an initial value of 12, what is
displayed?
23
Scanner x = new Scanner( System.in );
System.out.println( "Number?" );
int y = x.nextInt();
14. If y has an initial value of 26, what is
displayed?
if ( y > 10 )
y += 10;
37
15. If y has an initial value of 7, what is
displayed?
7
16. The code to the right does not compile.
The “else” is highlighted and the error
message is:
‘else’ without ‘if’
Why?
It says a If without an else because you need to
put } in the beginning of else then click enter
and put { then tab and put the line of code and
the the end of the code you need to put }
To close it.
17. Given that the above error is fixed
by the addition of two characters, what will
be displayed if the user enters 12?
24
18. If x has an initial value of -8, what is its
final value?
-3
19. If x has an initial value of 9, what is its
final value?
11
20. If x has an initial value of 15, what is its
final value?
if ( y > 20 )
y++;
System.out.println( y );
Scanner read = new Scanner( System.in );
System.out.println( "Number?" );
int a = read.nextInt();
if ( a > 10 && a < 20 )
{
a = 2 * a;
System.out.println( a );
}else
{
a--;
System.out.println( a );
}
// x is declared and assigned a value
if ( x > 10 || x < 20 )
x = x + 2;
if ( x < 10 || x > 20 )
x = x + 3;
// x is declared and assigned a value
if ( x > 10 && x < 20 )
x = x + 2;
page 3
17
20. If x has an initial value of 22, what is its
final value?
if ( x < 10 && x > 20 )
x = x + 3;
if ( x > 10 && x > 20 )
x = x + 10;
21. 32
22. If x has a final value of 6, what was its initial
value?
23. 6
page 4