Question

What value will be stored in the variable t after each of the following statements executes? A) t = (12 > 1);__________ B) t = (2 < 0);__________ C) t = (5 == (3 * 2));__________ D) t = (5 == 5);__________

Short answer

A) t = (12 > 1); B) t = (2 < 0); C) t = (5 == (3 * 2)); D) t = (5 == 5);

Step-by-step solution

A) Statement: t = (12 > 1);

First, we need to evaluate the expression "12 > 1", which checks if 12 is greater than 1. Since this is a true statement, the value 'true' will be stored in the variable 't' after executing this statement.

B) Statement: t = (2 < 0);

Next, we need to evaluate the expression "2 < 0", which checks if 2 is less than 0. Since this is a false statement, the value 'false' will be stored in the variable 't' after executing this statement.

C) Statement: t = (5 == (3 * 2));

Now, we need to evaluate the expression "5 == (3 * 2)", which checks if 5 is equal to the result of the multiplication of 3 and 2. Since 3 * 2 is equal to 6 and 5 is not equal to 6, this statement is false. The value 'false' will be stored in the variable 't' after executing this statement.

D) Statement: t = (5 == 5);

Lastly, we need to evaluate the expression "5 == 5", which checks if 5 is equal to 5. Since this is a true statement, the value 'true' will be stored in the variable 't' after executing this statement.

Key concepts

C++ Conditionals

Conditional statements in C++ are used to perform different actions based on different conditions. These are the core of decision making in programming. In C++, the most common conditional statements are if, else if, and else. To evaluate conditions, we often use relational and logical operators.

The if statement checks for a boolean condition: if the condition is true, the block of code inside the if is executed. If the condition is false, the program skips the block and moves on. An optional else if can follow an if statement to check another condition if the previous condition was false. An else statement can be used to execute a block of code when all preceding conditions were false.

For instance, considering the exercise given, the variable t would be involved in such a conditional statement to dictate the flow of a program based on its boolean value.

Boolean Expressions in C++

Boolean expressions in C++ are used to create conditions that result in either a true or false value. These expressions are fundamental in controlling the flow of a program with logical operators such as && (logical AND), || (logical OR), and ! (logical NOT).

In the exercise provided, the evaluations (12 > 1, 2 < 0, etc.) are boolean expressions. Such expressions are pivotal in conditionals where decisions are made depending on whether a condition is met or not. For instance, (5 == 5) directly translates to true, as 5 is indeed equal to 5.

Assignment Statements in C++

Assignment statements in C++ are used to assign values to variables. The assignment operator is represented by the equal sign =. The right side of the assignment operator is evaluated and its result is stored in the variable located on the left side.

In the context of the exercise, t = (12 > 1) is an assignment statement where the result of the boolean expression (12 > 1), which is true, is assigned to the variable t. It's crucial to use the correct assignment operator to update variables correctly and maintain coherent behavior within your program.

Comparing Values in C++

Comparing values in C++ is done using relational operators, such as == (equal to), != (not equal to), > (greater than), < (less than), >= (greater than or equal to), and <= (less than or equal to). These operators are used to create boolean expressions that return true or false.

For example, in the exercise, (5 == (3 * 2)) compares the values of 5 and 6 (result of 3 * 2) using the equality operator ==. As they are not equal, the expression evaluates to false. Understanding how to use these operators correctly is essential for comparing values and making decisions in C++.