Utilities library
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(C++11)(until C++20)
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(C++11)(until C++20)(C++17)
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.

[edit] Return value

T std::numeric_limits<T>::max()
/* non-specialized */ T()
bool true
signed char SCHAR_MAX
unsigned char UCHAR_MAX
wchar_t WCHAR_MAX
char8_t (C++20) UCHAR_MAX
char16_t (C++11) UINT_LEAST16_MAX
char32_t (C++11) UINT_LEAST32_MAX
short SHRT_MAX
unsigned short USHRT_MAX
unsigned int UINT_MAX
unsigned long ULONG_MAX
long long (C++11) LLONG_MAX
unsigned long long (C++11) ULLONG_MAX
float FLT_MAX
double DBL_MAX
long double LDBL_MAX

[edit] Example

Demonstrates the use of max() with some fundamental types and some standard library typedefs (the output is system-specific)

#include <limits>
#include <cstddef>
#include <iostream>
int main()
    std::cout << "short: " << std::dec << std::numeric_limits<short>::max()
              << " or " << std::hex << std::showbase << std::numeric_limits<short>::max() << '\n'
              << "int: " << std::dec << std::numeric_limits<int>::max()
              << " or " << std::hex << std::numeric_limits<int>::max() << '\n' << std::dec
              << "streamsize: " << std::dec << std::numeric_limits<std::streamsize>::max()
              << " or " << std::hex << std::numeric_limits<std::streamsize>::max() << '\n'
              << "size_t: " << std::dec << std::numeric_limits<std::size_t>::max()
              << " or " << std::hex << std::numeric_limits<std::size_t>::max() << '\n'
              << "float: " << std::numeric_limits<float>::max()
              << " or " << std::hexfloat << std::numeric_limits<float>::max() << '\n'
              << "double: " << std::defaultfloat << std::numeric_limits<double>::max()
              << " or " << std::hexfloat << std::numeric_limits<double>::max() << '\n';

Possible output:

short: 32767 or 0x7fff
int: 2147483647 or 0x7fffffff
streamsize: 9223372036854775807 or 0x7fffffffffffffff
size_t: 18446744073709551615 or 0xffffffffffffffff
float: 3.40282e+38 or 0x1.fffffep+127
double: 1.79769e+308 or 0x1.fffffffffffffp+1023

[edit] See also

[static] (C++11)
returns the lowest finite value of the given type
(public static member function) [edit]
returns the smallest finite value of the given type
(public static member function) [edit]