All Flashcards

What are the steps to reverse a string using a loop?

Initialize an empty string. 2. Iterate through the original string from the last character to the first. 3. Append each character to the new string.

What are the general steps for using a while loop?

Initialize a counter variable. 2. Write the while loop condition. 3. Include the code to be executed within the loop. 4. Update the counter variable inside the loop.

What are the general steps for using a for loop?

Initialize the loop variable in the for loop declaration. 2. Define the loop condition. 3. Specify the increment/decrement operation. 4. Include the code to be executed within the loop.

What are the steps to trace a loop?

Create a table with variables. 2. Execute each line of code. 3. Update the table with the new values. 4. Check the loop condition.

What are the steps to find a specific substring?

Iterate through the string. 2. Extract a substring of the same length as the target substring. 3. Compare the extracted substring with the target substring. 4. If they are equal, return true; otherwise, continue.

How is iteration applied in data processing?

Iterating through lists or arrays to perform calculations or transformations on each element.

How is iteration applied in searching algorithms?

Iterating through a dataset to find a specific element that satisfies a given condition.

How is iteration used to validate user input?

Loops can be used to repeatedly prompt the user for input until it meets certain criteria.

How is iteration used in game development?

Updating game state, processing user input, and rendering graphics.

How is iteration used in web scraping?

Extracting data from multiple web pages by iterating through a list of URLs.

How is string reversal used in real-world applications?

Can be used in cryptography or checking for palindromes.

What does the following code output?

java
int i = 0;
while (i < 3) {
 System.out.print(i);
 i++;
}

012

What does the following code output?

java
for (int i = 1; i <= 4; i++) {
 System.out.print(i + " ");
}

1 2 3 4

What does the following code output?

java
String str = "hello";
String reversed = "";
for (int i = str.length() - 1; i >= 0; i--) {
 reversed += str.charAt(i);
}
System.out.println(reversed);

olleh

What does the following code output?

java
int sum = 0;
for (int i = 0; i < 5; i++) {
 sum += i;
}
System.out.println(sum);

What does the following code output?

java
String str = "programming";
int count = 0;
for (int i = 0; i < str.length(); i++) {
 if (str.charAt(i) == 'g') {
 count++;
 }
}
System.out.println(count);

Identify the error in the following code:

java
int i = 0;
while (i < 5) {
 System.out.println("Hello");
}

The loop will run infinitely because i is never incremented.

Identify the error in the following code:

java
for (int i = 5; i >= 0;)
 System.out.println(i);

Missing the increment/decrement statement in the for loop, and missing curly braces. The condition will always be true, resulting in infinite loop.

What does the following code output?

java
int x = 1;
while (x < 10) {
  x = x + 3;
}
System.out.println(x);

What does the following code output?

java
String s = "APCSA";
for (int i = 0; i < s.length(); i++) {
  System.out.print(s.substring(i, i + 1));
}

APCSA

What does the following code output?

java
int n = 5;
for (int i = 1; i <= n; i++) {
  for (int j = 1; j <= i; j++) {
    System.out.print("*");
  }
  System.out.println();
}