Is true 0 or 1 in C++?

In C++, true is represented as 1.

C++ handles boolean values in a manner consistent with C. This means:

• False: Zero (0) is used to represent false.
• True: Non-zero values are interpreted as true. Importantly, true is stored as 1.

This is crucial for understanding how C++ handles logical operations and conditional statements.

C++ Boolean Representation

Boolean Value	Integer Representation
true	1
false	0

Examples

#include <iostream>

int main() {
  bool myTrueValue = true;
  bool myFalseValue = false;

  std::cout << "True is stored as: " << myTrueValue << std::endl;   // Outputs: True is stored as: 1
  std::cout << "False is stored as: " << myFalseValue << std::endl;  // Outputs: False is stored as: 0

  if (5) { // Any non-zero value is treated as true
    std::cout << "5 is considered true." << std::endl; // This line will be executed.
  }

  if (0) {
     std::cout << "0 is considered true." << std::endl; // This line will NOT be executed.
  } else {
     std::cout << "0 is considered false." << std::endl; // This line will be executed.
  }

  return 0;
}

Key Takeaways

• C++ retains C-style logic for boolean operations.
• Non-zero integers are interpreted as true.
• Zero is interpreted as false.
• true is stored as the integer 1.
• false is stored as the integer 0.