Output of Code
What is output?
int x = 9;
System.out.println(x / 2);
4
Which of the following is NOT a primitive data type?
String
The following is intended to count the number of times the number 87 is found in an array of test scores:
int [] d = / Assume array is initialized /;
int scoreCount = 0;
for (int i = 0; i < d.length; i++) {
if (/ Missing Code /)
scoreCount++;
}
System.out.println("Number of 87's: " + scoreCount);
Which of the following could replace / Missing Code / so that the code works as intended?
d[i] == 87
The following truth table matches which boolean condition?
A B ________
1 1 1
1 0 1
0 1 0
0 0 1
A || (!A && !B)
What are if statements used for in programs?
Making decisions
What is output?
System.out.println("The answer is: " + 5 + 19);
The answer is: 519
What's the largest data type?
String
Consider the following code, intended to count the number of words in the array with a length less than or equal to 6.
String vocabulary [] = / Array initialized with Strings /;
int c = 0;
for (int i = 0; i < vocabulary.length; i++) {
if ( / Missing Code /)
c++;
}
System.out.println("Number of words with length less than or equal to 6: " + c);
What could be used to replace / Missing Code / so that the code works as intended?
vocabulary[i].length() <= 6
The following is intended to count the number of times the number 87 is found in an array of test scores:
Consider the following boolean statement:
!( x >= y || w == z )
Which of the following will produce the same result?
x >= y || w != z
Which if statement below tests if letter holds R? (letter is a char variable)
if (letter == 'R')
Consider the following code:
double x = -97.6;
System.out.println(Math.abs(x));
What is output?
97.6
What does the String method charAt() do?
Returns the character at a certain location in the String object.
What does the following method do?
public static int mystery(int a[], int x) {
int c = 0;
for(int i = 0; i < a.length; i++) {
if (a[i] == x)
c++;
}
return c;
}
Returns a count of the number of times x appears in the array.
Assume that x and y are boolean variables and have been properly initialized.
!(x || y) || (x || y)
The result of evaluating the expression above is best described as:
always true
What are for loops in java?
controlled loop that allows a user to execute a block of a statements
What is output to the screen by the following code?
int num = 1987;
while (num > 0) {
num = num / 10;
System.out.print(num % 10 + " ");
}
8 9 1 0
What does the following code do?
String w3 = "aardvark";
System.out.println(w3.charAt(w3.length()-2));
Prints the second to last letter in the String.
What does the following algorithm do?
public static boolean mystery(int nums[]) {
for (int i = 1; i < nums.length; i++)
if (nums[i - 1] >= nums[i])
return false;
return true;
}
Returns true if each element of the array is greater than the element before.
Consider the code:
if ( y == 0 || x * y > 10)
Which of the following is an example of short circuit evaluation?
if y == 0 is true it doesn't evaluate x * y > 10
Consider the following code:
int [] a = {2, 6, 8, 10, 12, 14, 16, 18};
int sum = 0;
for(int i = 0; i < a.length; i++) {
if ( i%3 == 0 )
sum += a[i];
}
System.out.println(sum);
What is output?
28
What is output to the screen by the following code?
int c = 2;
while (c < 6) {
System.out.print((int)Math.pow (-1, c)+" ");
c++;
}
1 -1 1 -1
Consider the following code:
String w = "Rapunzel";
for (int i = 0; i < w.length(); i++) {
if ( i%4 != 2)
System.out.print(w.charAt(i) + " ");
}
What is output?
R a u n z l
What does the following algorithm do?
public static void mystery(int nums[]) {
for (int i = 0; i < nums.length; i++) {
if (nums[i] % 2 != 0)
nums[i]++;
}
}
Changes all the values in the array to even numbers.
What are Boolean expressions?
True or false
What is output by the following code?
for (int i = 0; i <= 5; i++) {
System.out.print(i + " ");
}
0 1 2 3 4 5