std::numeric_limits<T>::max
From cppreference.com
< cpp | types | numeric limits
| Defined in header <limits>
|
||
| static T max() throw(); |
(until C++11) | |
| static constexpr T max() noexcept; |
(since C++11) | |
Returns the maximum finite value representable by the numeric type T. Meaningful for all bounded types.
Return value
T
|
std::numeric_limits<T>::max() |
| /* non-specialized */ | T() |
| bool | true |
| char | CHAR_MAX |
| signed char | SCHAR_MAX |
| unsigned char | UCHAR_MAX |
| wchar_t | WCHAR_MAX |
| char8_t (since C++20) | UCHAR_MAX |
| char16_t (since C++11) | UINT_LEAST16_MAX |
| char32_t (since C++11) | UINT_LEAST32_MAX |
| short | SHRT_MAX |
| unsigned short | USHRT_MAX |
| int | INT_MAX |
| unsigned int | UINT_MAX |
| long | LONG_MAX |
| unsigned long | ULONG_MAX |
| long long (since C++11) | LLONG_MAX |
| unsigned long long (since C++11) | ULLONG_MAX |
| float | FLT_MAX |
| double | DBL_MAX |
| long double | LDBL_MAX |
Example
Demonstrates the use of max() with some fundamental types and some standard library typedefs (the output is system-specific):
Run this code
#include <cstddef> #include <iostream> #include <limits> #include <string_view> #include <type_traits> template<typename T> void print_max_twice(std::string_view type) { constexpr T max_value {std::numeric_limits<T>::max()}; std::cout << type << ": "; if constexpr (std::is_floating_point_v<T>) std::cout << std::defaultfloat << max_value << " or " << std::hexfloat << max_value << '\n'; else std::cout << std::dec << static_cast<unsigned long long>(max_value) << " or " << std::hex << static_cast<unsigned long long>(max_value) << '\n'; } int main() { std::cout << std::showbase; print_max_twice<bool>("bool"); print_max_twice<short>("short"); print_max_twice<int>("int"); print_max_twice<std::streamsize>("streamsize"); print_max_twice<std::size_t>("size_t"); print_max_twice<char>("char"); print_max_twice<char16_t>("char16_t"); print_max_twice<wchar_t>("wchar_t"); print_max_twice<float>("float"); print_max_twice<double>("double"); print_max_twice<long double>("long double"); }
Possible output:
bool: 1 or 0x1 short: 32767 or 0x7fff int: 2147483647 or 0x7fffffff streamsize: 9223372036854775807 or 0x7fffffffffffffff size_t: 18446744073709551615 or 0xffffffffffffffff char: 127 or 0x7f char16_t: 65535 or 0xffff wchar_t: 2147483647 or 0x7fffffff float: 3.40282e+38 or 0x1.fffffep+127 double: 1.79769e+308 or 0x1.fffffffffffffp+1023 long double: 1.18973e+4932 or 0xf.fffffffffffffffp+16380
See also
| [static] (C++11) |
returns the lowest finite value of the given type (public static member function) |
| [static] |
returns the smallest finite value of the given type (public static member function) |