EECS1021 Quiz 1

[1 mark] What is the console output of the following lines of Java code?

boolean b1 = false;
boolean b2 = false;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = true;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b1 = true;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = false;				
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));

=== false false === false true === true true === false true

===
false false
===
true false
===
true true
===
false true

===
false false
===
false true
===
true true
===
true false

===
false false
===
true false
===
true true
===
true false

[1 mark] What is the console output of the following lines of Java code?

boolean b1 = false;
boolean b2 = true;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = false;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b1 = true;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = true;				
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));

=== false true === false false === false true === true true

===
false true
===
false false
===
true false
===
true true

===
true false
===
false false
===
false true
===
true true

===
true false
===
false false
===
true false
===
true true

[1 mark] What is the console output of the following lines of Java code?

boolean b1 = true;
boolean b2 = false;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = true;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b1 = false;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = false;				
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));

=== false true === true true === false true === false false

===
false true
===
true true
===
true false
===
false false

===
true false
===
true true
===
false true
===
false false

===
true false
===
true true
===
true false
===
false false

[1 mark] What is the console output of the following lines of Java code?

boolean b1 = true;
boolean b2 = true;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = false;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b1 = false;
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));
b2 = true;				
System.out.println("===");  
System.out.println((b1 && b2) + " " + (b1 || b2));

=== true true === false true === false false === false true

===
true true
===
false true
===
false false
===
true false

===
true true
===
true false
===
false false
===
false true

===
true true
===
true false
===
false false
===
true false

[1 mark] What is the console output of the following lines of Java code?

boolean p = false;
boolean q = false;
boolean conjunction = p && q;
boolean disjunction = p || q;
System.out.println("===");
System.out.println(!conjunction);
System.out.println(!disjunction);
p = true;
System.out.println("===");
System.out.println(!conjunction);
System.out.println(!disjunction);

=== true true === true true
```
===
true
true
===
true
false
```
```
===
false
false
===
false
false
```
```
===
false
false
===
false
true
```

[1 mark] What is the console output of the following lines of Java code?

boolean p = false;
boolean q = true;
boolean conjunction = p && q;
boolean disjunction = p || q;
System.out.println("===");
System.out.println(!conjunction);
System.out.println(!disjunction);
p = true;
System.out.println("===");
System.out.println(!conjunction);
System.out.println(!disjunction);

=== true false === true false
```
===
true
false
===
false
false
```
```
===
false
true
===
false
true
```
```
===
false
true
===
true
true
```

[1 mark] What is the console output of the following lines of Java code?

boolean p = true;
boolean q = false;
boolean conjunction = p && q;
boolean disjunction = p || q;
System.out.println("===");
System.out.println(!disjunction);
System.out.println(!conjunction);
q = true;
System.out.println("===");
System.out.println(!disjunction);
System.out.println(!conjunction);

=== false true === false true
```
===
false
true
===
false
false
```
```
===
true
false
===
true
false
```
```
===
true
false
===
true
true
```

[1 mark] What is the console output of the following lines of Java code?

boolean p = true;
boolean q = true;
boolean conjunction = p && q;
boolean disjunction = p || q;
System.out.println("===");
System.out.println(!conjunction);
System.out.println(!disjunction);
p = false;
System.out.println("===");
System.out.println(!conjunction);
System.out.println(!disjunction);

=== false false === false false
```
===
false
false
===
true
false
```
```
===
true
true
===
true
true
```
```
===
true
true
===
false
true
```

[1 mark] Assume that we already declare an int variable called i. Which of the following boolean expressions always evaluates to true (despite the value of i)?
1. ```
i >= 5 && 10 >= i
```
2. i >= 5 || 10 >= i
3. ```
i < 5 && 10 < i
```
4. ```
i < 5 || 10 < i
```

[1 mark] Assume that we already declare an int variable called i. Which of the following boolean expressions always evaluates to true (despite the value of i)?
1. ```
17 >= i && i >= 4
```
2. 17 >= i || i >= 4
3. ```
17 < i && i < 4
```
4. ```
17 < i || i < 4
```

[1 mark] Assume that we already declare an int variable called i. Which of the following boolean expressions always evaluates to false (despite the value of i)?
1. ```
i >= 5 && 10 >= i
```
2. ```
i >= 5 || 10 >= i
```
3. i < 5 && 10 < i
4. ```
i < 5 || 10 < i
```

[1 mark] Assume that we already declare an int variable called i. Which of the following boolean expressions always evaluates to false (despite the value of i)?
1. ```
17 >= i && i >= 4
```
2. ```
17 >= i || i >= 4
```
3. 17 < i && i < 4
4. ```
17 < i || i < 4
```

[1 mark] What is the console output of the following lines of Java code?

int i = 5;
int j = 7;
int k = 9;
String s = "Hello ";
System.out.println(s + i + j + k);
System.out.println((s + i) + j + k);
System.out.println(s + (i + j) + k);

Hello 579 Hello 579 Hello 129
```
Hello 579
Hello 516
Hello 129
```
```
Hello 21
Hello 516
Hello 129
```
```
Hello 579
Hello 579
Hello 579
```
There is a compile-time error in the above code, so it simply cannot be run to produce console output.

[1 mark] What is the console output of the following lines of Java code?

int i = 11;
int j = 12;
int k = 13;
String s = "Hello ";
System.out.println(s + i + j + k);
System.out.println((s + i) + j + k);
System.out.println(s + (i + j) + k);

Hello 111213 Hello 111213 Hello 2313
```
Hello 111213
Hello 1125
Hello 2313
```
```
Hello 36
Hello 1125
Hello 2313
```
```
Hello 111213
Hello 111213
Hello 111213
```
There is a compile-time error in the above code, so it simply cannot be run to produce console output.

[1 mark] What is the console output of the following lines of Java code?
```
int i = 25;
int j = 11;
int k = 3;
System.out.println(((i % j) * (j / k)) % 4);
```
1. ```
0
```
2. 1
3. ```
2
```
4. ```
3
```
5. ```
4
```
6. There is a compile-time error in the above code, so it simply cannot be run to produce console output.

[1 mark] What is the console output of the following lines of Java code?
```
int i = 37;
int j = 11;
int k = 3;
System.out.println(((i % j) * (j / k)) % 4);
```
1. 0
2. ```
1
```
3. ```
2
```
4. ```
3
```
5. ```
4
```
6. There is a compile-time error in the above code, so it simply cannot be run to produce console output.

[1 mark] What is the console output of the following lines of Java code?

int i = 13;
int j = 2;
System.out.println(i / j);
System.out.println( (double) (i  / j));
System.out.println(((double)  i) / j );
System.out.println( (double)  i  / j );

6 6.0 6.5 6.5
```
6.5
6.5
6.5
6.5
```
```
6
6.0
6.0
6.0
```
```
6
6.0
6.5
6.0
```
There is a compile-time error in the above code, so it simply cannot be run to produce console output.

[1 mark] What is the console output of the following lines of Java code?

int i = 14;
int j = 4;
System.out.println(i / j);
System.out.println( (double) (i  / j));
System.out.println(((double)  i) / j );
System.out.println( (double)  i  / j );

3 3.0 3.5 3.5
```
3.5
3.5
3.5
3.5
```
```
3
3.0
3.0
3.0
```
```
3
3.0
3.5
3.0
```
There is a compile-time error in the above code, so it simply cannot be run to produce console output.

[1 mark] What is the console output of the following lines of Java code?

double a = 3.1415926;  
double b = (int) a; 
System.out.println(b);

int c = (int) a; 
System.out.println(c);

double d = (c * 5) / 2; 
System.out.println(d);

d = (b * 5) / 2;
System.out.println(d);

3.0 3 7.0 7.5
```
3.0
3.0
7.0
7.5
```
```
3.0
3.0
7.5
7.5
```
```
3
3
7.0
7.0
```

[1 mark] What is the console output of the following lines of Java code?

double a = 3.1415926;  
double b = (int) a; 
System.out.println(b);

int c = (int) a; 
System.out.println(c);

double d = (c * 9) / 2; 
System.out.println(d);

d = (b * 9) / 2;
System.out.println(d);

3.0 3 13.0 13.5
```
3.0
3.0
13.0
13.5
```
```
3.0
3.0
13.5
13.5
```
```
3
3
13.0
13.0
```

[1 mark] What is the console output of the following lines of Java code?

double a = 3.4;
double b = ((int) a) * 3; 
System.out.println(b);

double c = ((int) a) + 2.7; 
System.out.println(c);

double d = (( (int) c ) * 3) / 2; 
System.out.println(d);

d = (b * 3) / 2;
System.out.println(d);

9.0 5.7 7.0 13.5
```
10.0
6.0
9.0
15.0
```
```
10.2
6.1
9.15
15.3
```
```
9
5
7
13
```

[1 mark] What does the equal sign (=) mean in Java?
1. The assignment operator.
2. The relational comparison operator.
3. The arithmetic quotient operator.
4. The arithmetic remainder operator.

[1 mark] What does the equal-equal sign (==) mean in Java?
1. The assignment operator.
2. The relational comparison operator.
3. The arithmetic quotient operator.
4. The arithmetic remainder operator.

[1 mark] What does the percentage sign (%) mean in Java?
1. The assignment operator.
2. The relational comparison operator.
3. The arithmetic quotient operator.
4. The arithmetic remainder operator.

[1 mark] What does the operator && mean in Java?
1. The logical conjunction operator.
2. The logical disjunction operator.
3. The logical negation operator.
4. The concatenation operator.

[1 mark] What does the operator || mean in Java?
1. The logical conjunction operator.
2. The logical disjunction operator.
3. The logical negation operator.
4. The concatenation operator.

[1 mark] What does the operator || mean in Java?
1. The logical conjunction operator.
2. The logical disjunction operator.
3. The logical negation operator.
4. The concatenation operator.

[1 mark] Which one of the following expressions contains type error(s) so that it does not compile?
1. ```
"I " + "Love " + 1021
```
2. ```
((double) 11 / 3) + " is what?"
```
3. ```
((13 % 3) + "234") + 56 + ("(13 % 3) * 234")
```
4. ((13 % 3) + "234") / 56 + ((13 % 3) * 234)
5. All of the above expressions contain some type error(s).
6. None of the above expressions contain some type error(s).

York University

Solutions of EECS1021 Quiz 1

The correct answer is in bold red.