Understanding Selection Structures

What is the basic structure of an if statement?

• if { condition } { // code to execute }

• if condition { // code to execute }

• if (condition) { // code to execute }

• if (condition) // code to execute

How do you write an if statement in Python?

• if (condition) do_something()

• if condition do_something()

• if condition: do_something()

• if: condition do_something()

What is the purpose of an else statement?

• To execute code only when the if condition is true.

• To define a block of code that always runs regardless of conditions.

• To replace the if statement entirely.

• The purpose of an else statement is to define a block of code that runs when the if condition is false.

Explain the use of elif in Python.

• 'elif' is a keyword that terminates a loop in Python.

• The 'elif' statement is used to define functions in Python.

• The 'elif' statement is only used for error handling in Python.

• The 'elif' statement in Python allows for multiple conditional checks in an if-else structure.

What will the following code output: if x > 10: print('High') else: print('Low')?

• Always 'Low' regardless of x's value.

• 'High' if x < 10, 'Low' otherwise.

• Depends on the value of x; 'High' if x > 10, 'Low' otherwise.

• Always 'High' regardless of x's value.

What is typecasting and why is it used?

• Typecasting is the conversion of a variable from one data type to another, used to ensure compatibility and prevent errors.

• Typecasting is the process of changing a variable's name.

• Typecasting refers to the encryption of data types.

• Typecasting is used to increase the size of a variable.

How do you convert a string to an integer in Python?

• Use int('string') to convert a string to an integer.

• Use eval('string') to get an integer from a string.

• Apply float('string') for conversion to integer.

• Use str('string') to convert a string to an integer.

What is the difference between implicit and explicit typecasting?

• Implicit typecasting is automatic and done by the compiler, while explicit typecasting is manually done by the programmer.

• Explicit typecasting is done by the compiler, while implicit typecasting is done by the programmer.

• Implicit typecasting requires user intervention, while explicit typecasting is automatic.

• Implicit typecasting can only be used with integers, while explicit typecasting can be used with all data types.

What are placeholders in programming?

• Placeholders are fixed values that cannot be changed.

• Placeholders are symbols or variables that reserve space for values to be provided later in programming.

• Placeholders are used to define the final output of a program.

• Placeholders are specific data types that must be declared before use.

How do you use placeholders in a formatted string?

• Placeholders are not allowed in formatted strings.

• Use square brackets for placeholders like [name] in Python.

• Use placeholders in formatted strings by using syntax specific to the programming language, such as f'Hello, {name}!' in Python or `${variable}` in JavaScript.

• Use parentheses for placeholders, e.g., (name) in JavaScript.