C++ Boolean Expressions
Boolean Expressions
A Boolean expression is a piece of code that compares values or variables and returns a boolean value:
1 (true) or 0 (false).
Boolean expressions are the foundation of decision making in programming - they let your program decide what to do based on whether something is true or false.
You can use a comparison operator, such as the greater than (>) operator,
to find out if an expression (or variable) is true or false:
Example
int x = 10;
int y = 9;
cout << (x > y); // returns 1 (true), because 10 is higher than 9
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Or even easier:
In the examples below, we use the equal to (==) operator to evaluate an expression:
Example
int x = 10;
cout << (x == 10); // returns 1 (true), because the value
of x is equal to 10
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Store the Result in a Boolean Variable
You can also store the result of a comparison in a bool variable:
Example
Store the result of x > y in a boolean variable, and print it:
int x = 10;
int y = 9;
bool isGreater = x > y;
cout << isGreater; // returns 1 (true)
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Note: It is up to you whether you store the result of a comparison in a boolean variable
or use the comparison directly.
Storing the result can make your code easier to read, especially if you want to reuse it.