bool类型

bool类型

//与C语言相比，C++添加了一种基本类型 —— bool类型，用来表示true和false
//true和false是字面值，可以通过转变为int类型，true是1，false是0
#include <iostream>

using std::cout;
using std::endl;

int main()
{
  int x = true;
  int y = false;
  
  cout << "true = " << true << endl;
  cout << "x = " << x << endl;
  cout << "false = " << false << endl;
  cout << "y = " << y << endl;
  return 0;
}

//任何数字或指针值都可以隐式转换为bool值
//任何非零值都将转换为true，而零值转换为false
#include <iostream>

using std::cout;
using std::endl;

int main()
{
  bool x = -100;
  bool y = 0;
  bool z = 100;
  bool yes = true;
  bool no = false;

  cout << "x = " << x << endl;
  cout << "y = " << y << endl;
  cout << "z = " << z << endl;
  cout << "yes = " << yes << endl;
  cout << "no = " << no << endl;

  return 0;
}

//一个bool类型的数据占据的内存空间大小为1
#include <iostream>

using std::cout;
using std::endl;

int main()
{
  cout << "sizeof(bool) = " << sizeof(bool) << endl;
  cout << "sizeof(true) = " << sizeof(true) << endl;
  cout << "sizeof(false) = " << sizeof(false) << endl;

  return 0;
}