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C++ Booleans


C++ Booleans

Very often, in programming, you will need a data type that can only have one of two values, like:

  • YES / NO
  • ON / OFF
  • TRUE / FALSE

For this, C++ has a bool data type, which can take the values true (1) or false (0).


Boolean Values

A boolean variable is declared with the bool keyword and can only take the values true or false:

Example

bool isCodingFun = true;
bool isFishTasty = false;
cout << isCodingFun;  // Outputs 1 (true)
cout << isFishTasty;  // Outputs 0 (false)
Run example »

From the example above, you can read that a true value returns 1, and false returns 0.

However, it is more common to return boolean values from boolean expressions (see next page).