Level 1 - Intro to Java

Question 1

What is the escape sequence for creating a new line?

Answer 1

What is the escape sequence for creating a new line?

\n

Question 2

What symbol terminates every line?

Answer 2

What symbol terminates every line?

;

Question 3

Write two lines of code where the first prints “Hello”, the second prints “world”, and the net result is that they print together exactly as follows:
Helloworld

Answer 3

Write two lines of code where the first prints “Hello”, the second prints “world”, and the net result is that they print together exactly as follows:
Helloworld

System.out.print(“Hello”);
System.out.println(“world”);

Question 4

In the following two lines of code, state which line is initializing and which is declaring.
int siv;
siv = 14;

Answer 4

int siv; //declaring

siv = 14; //initializing

Question 5

What is output by the following code?
int x = 22;
int y = 6;
System.out.println(x % y);

Answer 5

4

Question 6

What are the data types that we are able to input from the keyboard?

Answer 6

String, Int, double

Question 7

Which of the following is illegal?

a. double d = 27;
b. int i = 203.932;

Answer 7

b.
int i = 203.932;
//int types can't hold decimals

Question 8

What are the three different types of primitive variables that we have learned so far?

Answer 8

String, int, and double

Question 9

Declare a string called myString that initializes to: Computer Science

Answer 9

String myString = "Computer Science";
//don't forget the quotes

Question 10

What will the following code print out?

String s = “Mona Lisa”;
System.out.println(s.length( ));

Answer 10

String s = “Mona Lisa”;
System.out.println(s.length( ));

//Outputs
9
//remember to count the space between words

Question 11

What is the escape sequence for a tab?

Answer 11

What is the escape sequence for a tab?

\t

Question 12

What does this mean: 1.45667E24

Answer 12

What does this mean: 1.45667E24

1.45667 x 10^24

Question 13

What would the following print out:

System.out.println( “my dog has fleas”.substring(4) );

Answer 13

What would the following print out:
System.out.println( “my dog has fleas”.substring(4) );

og has fleas

//start at character with index 4 until the end

Question 14

What would the following print out:

System.out.println( “my dog has fleas”.substring(5, 9) );

Answer 14

g ha

//started at index 4 and end just before index 9

Question 15

What is another way to write:

x = x + 1;

Answer 15

x++ or ++x

Question 16

What is this compound operator short for:

x+=y-4;

Answer 16

x = x + (y-4);

Question 17

1%3 = ?

Answer 17

0

Question 18

What is the scanner method to look for a String input

Answer 18

nextLine()

Question 19

How does one represent pi using the math class

Answer 19

Math.PI

//PI is all caps and not () follow it

Question 20

Which of these lines will result in an error:
A). double x = 14.7;
Int y = x;

B). int x = 14;
double y = x;

Answer 20

A

//there is a potential loss of precision.

Question 21

How does one add a comment for personal use?

Answer 21

//