numeric_limits 类模板提供了一种标准化的方式来查询算术类型的各种属性
比如
std::numeric_limits<int>::max()
numeric_limits 提供了专有的信息
#include <limits> #include <iostream> int main() { std::cout << "type\t│ lowest()\t│ min()\t\t│ max()\n" << "bool\t│ " << std::numeric_limits<bool>::lowest() << "\t\t│ " << std::numeric_limits<bool>::min() << "\t\t│ " << std::numeric_limits<bool>::max() << '\n' << "uchar\t│ " << +std::numeric_limits<unsigned char>::lowest() << "\t\t│ " << +std::numeric_limits<unsigned char>::min() << "\t\t│ " << +std::numeric_limits<unsigned char>::max() << '\n' << "int\t│ " << std::numeric_limits<int>::lowest() << "\t│ " << std::numeric_limits<int>::min() << "\t│ " << std::numeric_limits<int>::max() << '\n' << "float\t│ " << std::numeric_limits<float>::lowest() << "\t│ " << std::numeric_limits<float>::min() << "\t│ " << std::numeric_limits<float>::max() << '\n' << "double\t│ " << std::numeric_limits<double>::lowest() << "\t│ " << std::numeric_limits<double>::min() << "\t│ " << std::numeric_limits<double>::max() << '\n'; }
