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| Static constants | ||||
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numeric_limits::min | ||||
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| Helper types | ||||
Defined in header <limits> | ||
static T min()throw(); | (until C++11) | |
staticconstexpr T min()noexcept; | (since C++11) | |
Returns the minimum finite value representable by the numeric typeT.
For floating-point types with denormalization,min() returns the minimum positive normalized value.Note that this behavior may be unexpected, especially when compared to the behavior ofmin() for integral types.To find the value that has no values less than it, uselowest().(since C++11)
min() is only meaningful for bounded types and for unbounded unsigned types.
T | std::numeric_limits<T>::min() |
| /* non-specialized */ | T() |
| bool | false |
| char | CHAR_MIN |
| signedchar | SCHAR_MIN |
| unsignedchar | 0 |
| wchar_t | WCHAR_MIN |
| char8_t(since C++20) | 0 |
| char16_t(since C++11) | 0 |
| char32_t(since C++11) | 0 |
| short | SHRT_MIN |
| unsignedshort | 0 |
| int | INT_MIN |
| unsignedint | 0 |
| long | LONG_MIN |
| unsignedlong | 0 |
| longlong(since C++11) | LLONG_MIN |
| unsignedlonglong(since C++11) | 0 |
| float | FLT_MIN |
| double | DBL_MIN |
| longdouble | LDBL_MIN |
Demonstrates the use with typedef types, and the difference in the sign of the result between integer and floating-point types:
#include <cstddef>#include <iomanip>#include <iostream>#include <limits> // we want to print char types as an integer without leading Fsauto p(auto x){return x;}auto p(char x){return x&static_cast<unsignedchar>(-1);} template<typename T>void print_one(std::string_view type_name){constexpr T min=std::numeric_limits<T>::min(); std::cout<<std::dec<<std::defaultfloat<<std::setw(14)<< type_name<<" ("<<std::setw(2)<< sizeof(T)<<" bytes): "<<+min; ifconstexpr(min!=0)std::cout<<" or "<<std::showbase<<std::hex<<std::hexfloat<< p(min); std::cout<<'\n';} #define SHOW(T) print_one<T>(#T) int main(){ SHOW(bool); SHOW(char); SHOW(unsignedchar); SHOW(short); SHOW(unsignedshort); SHOW(signed); SHOW(unsigned); SHOW(std::ptrdiff_t); SHOW(std::size_t); SHOW(float); SHOW(double); SHOW(longdouble);}
Possible output:
bool ( 1 bytes): 0 char ( 1 bytes): -128 or 0x80 unsigned char ( 1 bytes): 0 short ( 2 bytes): -32768 or 0x8000unsigned short ( 2 bytes): 0 signed ( 4 bytes): -2147483648 or 0x80000000 unsigned ( 4 bytes): 0std::ptrdiff_t ( 8 bytes): -9223372036854775808 or 0x8000000000000000 std::size_t ( 8 bytes): 0 float ( 4 bytes): 1.17549e-38 or 0x1p-126 double ( 8 bytes): 2.22507e-308 or 0x1p-1022 long double (16 bytes): 3.3621e-4932 or 0x8p-16385
[static](C++11) | returns the lowest finite value of the given type, i.e. the most negative value for signed types,0 for unsigned types (public static member function)[edit] |
[static] | returns the smallest positive subnormal value of the given floating-point type (public static member function)[edit] |
[static] | returns the largest finite value of the given type (public static member function)[edit] |
