Question

Write an if statement that assigns 100 to x when y is equal to 0.

Short answer

Question: Write an if statement that assigns the value 100 to a variable x when the value of another variable y is equal to 0. Answer: ```python if y == 0: x = 100 ```

Step-by-step solution

Write the if statement

To write the if statement, first start with the keyword "if" followed by the condition that y is equal to 0. In most programming languages, the equality operator is "==". ```python if y == 0: ```

Assign the value 100 to x

Inside the if statement block, write the assignment statement to assign the value 100 to the variable x. ```python x = 100 ```

Combine the steps

Now, combine the if statement and the assignment statement in a single code block. ```python if y == 0: x = 100 ``` This code checks whether the value of y is equal to 0. If the condition is true, it assigns the value 100 to the variable x. If the condition is false, nothing happens to the variable x.

Key concepts

Conditional Statements

In the world of programming, conditional statements are fundamental constructs that allow you to perform different actions based on specific conditions. In C++, the `if` statement is a common way to implement this. The basic syntax starts with the keyword `if`, followed by a condition enclosed in parentheses. This condition is an expression that evaluates to either true or false.

If the condition is true, then the code block contained within the curly braces `{}` following the statement is executed. If the condition is false, the block is skipped. In our problem, we check if `y` is equal to 0 using the `==` operator, a common comparison operator used to test equality.

• Syntax: `if (condition) { /* code to execute if condition is true */ }`
• Comparison Operator: `==` is used to compare values for equality.

Remember, the condition must be placed within parentheses, and any actions that follow when the condition is met are enclosed in curly braces. This structure helps in easily reading and understanding the flow of the program.

Assignment Operations

Assignment operations in C++ are used to assign a value to a variable. The assignment operator is the `=` sign, which places the specified value on the right-hand side into the variable on the left-hand side. In our exercise, we assign the value `100` to the variable `x` if the condition specified in the `if` statement is true.

• Syntax: `x = 100;`
• Left-Hand Side (LHS): The variable that receives the value.
• Right-Hand Side (RHS): The value or expression to be assigned to the LHS.

This operation is simple but powerful; it allows the dynamic change of a variable's value based on conditions, making your program responsive to various inputs. It's important to always ensure that the variable (LHS) is declared before assignment to avoid errors.

Basic Syntax in C++

Understanding basic syntax in C++ is crucial for writing error-free code. C++ syntax refers to the set of rules defining how programs written in C++ should be constructed. These rules govern various aspects, including how conditional statements and assignment operations are executed.

Some key rules and concepts to remember include:

• Statements in C++ usually end with a semicolon (`;`).
• Curly braces `{}` are used to denote a block of code, such as the body of an `if` statement.
• Comments can be added using `//` for single-line or `/* */` for multi-line comments, helping to explain code logic.
• Indentation is not strictly necessary for code execution, but it is crucial for readability.

C++ is case-sensitive, meaning that variables and functions must be used consistently according to their defined cases (e.g., `Variable`, `VARIABLE`, and `variable` would be seen as different). Adhering to these syntax rules ensures that your code is not only correct but also maintainable and readable.