Mastering Python Loops, Lists and Strings

What is the syntax for a for loop in Python?

• foreach variable in sequence:

• for each variable in sequence:

• for (variable; condition; increment)

• for variable in sequence:

How do you create a while loop that runs until a variable reaches 10?

• while (variable = 10) { variable++; }

• while (variable < 10) { variable++; }

• while (variable != 10) { variable++; }

• while (variable > 10) { variable--; }

What method would you use to convert a string to lowercase in Python?

• lowercase()

• convertToLower()

• .lower()

• .toLowerCase()

How can you create a list of squares of numbers from 1 to 10 using list comprehension?

• [x^2 for x in range(1, 10)]

• [x**2 for x in range(1, 11)]

• [x*2 for x in range(1, 11)]

• [x**3 for x in range(1, 11)]

What is the output of the following code: for i in range(5): print(i)?

• 0 1 2 3 4

• 3.5

• -1

• 5

Explain how nested loops work with an example.

• For example, in a 2D array, an outer loop can iterate through rows, while an inner loop iterates through columns: for (int i = 0; i < rows; i++) { for (int j = 0; j < columns; j++) { process(array[i][j]); } }

• An outer loop cannot access the inner loop's variables.

• Nested loops can only be used with single-dimensional arrays.

• Nested loops are not efficient for processing data.

What string method would you use to find the length of a string?

• length()

• count()

• len()

• size()

How do you format a string using f-strings in Python?

• Use f'string {variable}' to format a string with f-strings.

• Format strings with f-strings using 'string + variable'.

• Use f'string {variable}' only for numbers.

• Use 'string {variable}' without f-prefix.

How can you check if a substring exists within a string?

• Use the 'indexOf' method in Python

• Convert the string to uppercase and compare

• Check the length of the string

• Use the 'in' operator in Python or 'contains' method in Java.

How do you append an item to a list in Python?

• Add the item using the + operator, e.g., my_list = my_list + [item].

• Use the extend() method, e.g., my_list.extend([item]).

• Use the insert() method, e.g., my_list.insert(index, item).

• Use the append() method, e.g., my_list.append(item).