Boolalpha

Boolalpha is a standard C++ iostream manipulator that controls how boolean values are formatted on streams. When enabled, booleans are written as the words true and false instead of the numeric 1 and 0. The setting also affects input: with boolalpha active, operator>> expects the tokens true or false to assign to boolean variables.

Usage is simple: it is applied to a stream by inserting std::boolalpha, for example, std::cout << std::boolalpha << someBool; This will print true or false. To revert to the default numeric representation, use std::noboolalpha, for instance std::cout << std::noboolalpha << anotherBool;. The effect persists for that stream until it is changed again.

Boolalpha is defined in the C++ standard library (included via headers like <iostream>, and often <iomanip> for related manipulators). It is part of the ios_base formatting flags and interacts with both output and input streams. In practice, it is commonly used for human-readable output in logs, configuration displays, or simple serialization where textual boolean values are preferred over numeric ones.

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