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Name the 8 primitive data types in Java and indicate which type can be added to an int variable without producing an error or a value of type other than int.
What is the minimum number of characters in the expression #3do* that must be
removed for it to represent a legal name for a variable in Java?
What does the following code print?
public class Main {
public static void main(String[] args) {
double y = 1;
double x = (27 % 7) + (y += (15.6 % 4.1));
System.out.println(x);
}
}
Convert 1101 to binary.
Write the 8-bit two's complement version of -100
Give an example of a "literal" for each of the following types: int, double, float, boolean, and char
What java keyword is used to indicate a constant value?
Convert the hexadecimal number 110101011011111000011100111 to hexadecimal.
Write the truth table for (P && Q) ^ (! R)
What does the following code print?
public class Main {
public static void main(String[] args) {
int x = 1;
int y = 2;
int z = 3;
System.out.println( z / y == x ? x : y);
System.out.println( 1.0 * x / 2);
}
}
What does the following print?
public class Main {
public static void main(String[] args) {
int x = 2 + 'B';
int y = 5;
switch (x) {
case 'B': System.out.print(1);
case 'C': System.out.print(2);
case 'D': System.out.print(y + y + "B");
default : System.out.print("B" + y + y);
}
if ((y > 4) && (y <= 6))
if (y == 6)
System.out.print("E");
else
System.out.print("F");
}
}
What will the following print?
public class Main {
public static void main(String[] args) {
int s = 0;
for (int d = 1; d < 50; d++) {
if (50 % d == 0)
s += d;
}
System.out.println(s);
}
}
What will the following print?
public class Main {
public static void main(String[] args) {
int s = '\u0052' - '\u0042';
System.out.println(s);
}
}
What will the following print?
public class Main {
public static void main(String[] args) {
char c = 'K';
c = (char) (((7 + (c - 'A') * 5) % 26) + 'A');
System.out.println(c);
}
}
What will the following print?
public class Main {
public static void main(String[] args) {
double pi = 3.1459;
System.out.printf("%.2f + \\\n %.1f" + "\"", pi, pi);
}
}
If a and b are int variables, and b != 0, circle the choices below that
equal a%b. (There may or may not be more than one.)
a) a - ( a / b ) * b b) ( a / b ) * b c) a - a / b d) (double) a / b - a / b
What does the following print?
public class Main {
public static void main(String[] args) {
int sum = 0;
int item = 0;
do {
item++;
sum += item;
if (sum > 4)
break;
} while (item < 5);
System.out.println(sum);
}
}
Suppose x, y, and z are of type int. Using an appropriate function from the Math class, write a single Java statement which defines a variable named max of type int and assigns it a value equal to the maximum of x, y, and z.
The following program was intended to check the discriminant of the quadratic
equation x^2 + 0.4x + 0.04 = 0 to say something about the number of solutions. The
output printed was "zero or two solutions", when we know there is only one solution
(namely, x = -0.2). Explain what went wrong.
public class Main {
public static void main(String[] args) {
double a = 1;
double b = 0.4;
double c = 0.04;
if (b*b - 4*a*c == 0) {
System.out.println("one solution");
}
else {
System.out.println("zero or two solutions");
}
}
}
Complete the following code so that a triangle of x's whose height and base match the user input is printed, as shown in the sample runs given.
public class Main {
public static void main(String[] args) {
int n = Integer.parseInt(args[0]);
}
}
Sample Runs: > java Main 5 <-- Note: this is a command to run the program, not output x xx xxx xxxx xxxxx > java Main 3 <-- Note: this is a command to run the program, not output x xx xxx
byte*, short*, int*, long, float, double, char*, boolean
4
10.3
10001001101
10011100
1, 1.0, 1.0F, true, 'a', respectively
final
6ADF0E7
P Q R (P&&Q) (!R) (P&&Q)^(!R) F F F F T T F F T F F F F T F F T T F T T F F F T F F F T T T F T F F F T T F T T F T T T T F T
1 0.5
10BB55F
43
16
F
3.15 + \ 3.1"
6
int max = Math.max(x, Math.max(y,z));
you can't compare doubles with ==, they are stored approximately
public class Main {
public static void main(String[] args) {
int n = Integer.parseInt(args[0]);
for (int row = 0; row < n; row++) {
for (int col = 0; col <= row; col++)
System.out.print('x');
System.out.println();
}
}
}