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Exact-width integer types | |
|  Integer types having exactly the specified width  | |
| typedef signed char | int8_t | 
| typedef unsigned char | uint8_t | 
| typedef signed int | int16_t | 
| typedef unsigned int | uint16_t | 
| typedef signed long int | int32_t | 
| typedef unsigned long int | uint32_t | 
| typedef signed long long int | int64_t | 
| typedef unsigned long long int | uint64_t | 
Integer types capable of holding object pointers | |
|  These allow you to declare variables of the same size as a pointer.  | |
| typedef int16_t | intptr_t | 
| typedef uint16_t | uintptr_t | 
Minimum-width integer types | |
|  Integer types having at least the specified width  | |
| typedef int8_t | int_least8_t | 
| typedef uint8_t | uint_least8_t | 
| typedef int16_t | int_least16_t | 
| typedef uint16_t | uint_least16_t | 
| typedef int32_t | int_least32_t | 
| typedef uint32_t | uint_least32_t | 
| typedef int64_t | int_least64_t | 
| typedef uint64_t | uint_least64_t | 
Fastest minimum-width integer types | |
|  Integer types being usually fastest having at least the specified width  | |
| typedef int8_t | int_fast8_t | 
| typedef uint8_t | uint_fast8_t | 
| typedef int16_t | int_fast16_t | 
| typedef uint16_t | uint_fast16_t | 
| typedef int32_t | int_fast32_t | 
| typedef uint32_t | uint_fast32_t | 
| typedef int64_t | int_fast64_t | 
| typedef uint64_t | uint_fast64_t | 
Greatest-width integer types | |
|  Types designating integer data capable of representing any value of any integer type in the corresponding signed or unsigned category  | |
| typedef int64_t | intmax_t | 
| typedef uint64_t | uintmax_t | 
Limits of specified-width integer types | |
|  C++ implementations should define these macros only when __STDC_LIMIT_MACROS is defined before <stdint.h> is included  | |
| #define | INT8_MAX 0x7f | 
| #define | INT8_MIN (-INT8_MAX - 1) | 
| #define | UINT8_MAX (__CONCAT(INT8_MAX, U) * 2U + 1U) | 
| #define | INT16_MAX 0x7fff | 
| #define | INT16_MIN (-INT16_MAX - 1) | 
| #define | UINT16_MAX (__CONCAT(INT16_MAX, U) * 2U + 1U) | 
| #define | INT32_MAX 0x7fffffffL | 
| #define | INT32_MIN (-INT32_MAX - 1L) | 
| #define | UINT32_MAX (__CONCAT(INT32_MAX, U) * 2UL + 1UL) | 
| #define | INT64_MAX 0x7fffffffffffffffLL | 
| #define | INT64_MIN (-INT64_MAX - 1LL) | 
| #define | UINT64_MAX (__CONCAT(INT64_MAX, U) * 2ULL + 1ULL) | 
Limits of minimum-width integer types | |
| #define | INT_LEAST8_MAX INT8_MAX | 
| #define | INT_LEAST8_MIN INT8_MIN | 
| #define | UINT_LEAST8_MAX UINT8_MAX | 
| #define | INT_LEAST16_MAX INT16_MAX | 
| #define | INT_LEAST16_MIN INT16_MIN | 
| #define | UINT_LEAST16_MAX UINT16_MAX | 
| #define | INT_LEAST32_MAX INT32_MAX | 
| #define | INT_LEAST32_MIN INT32_MIN | 
| #define | UINT_LEAST32_MAX UINT32_MAX | 
| #define | INT_LEAST64_MAX INT64_MAX | 
| #define | INT_LEAST64_MIN INT64_MIN | 
| #define | UINT_LEAST64_MAX UINT64_MAX | 
Limits of fastest minimum-width integer types | |
| #define | INT_FAST8_MAX INT8_MAX | 
| #define | INT_FAST8_MIN INT8_MIN | 
| #define | UINT_FAST8_MAX UINT8_MAX | 
| #define | INT_FAST16_MAX INT16_MAX | 
| #define | INT_FAST16_MIN INT16_MIN | 
| #define | UINT_FAST16_MAX UINT16_MAX | 
| #define | INT_FAST32_MAX INT32_MAX | 
| #define | INT_FAST32_MIN INT32_MIN | 
| #define | UINT_FAST32_MAX UINT32_MAX | 
| #define | INT_FAST64_MAX INT64_MAX | 
| #define | INT_FAST64_MIN INT64_MIN | 
| #define | UINT_FAST64_MAX UINT64_MAX | 
Limits of integer types capable of holding object pointers | |
| #define | INTPTR_MAX INT16_MAX | 
| #define | INTPTR_MIN INT16_MIN | 
| #define | UINTPTR_MAX UINT16_MAX | 
Limits of greatest-width integer types | |
| #define | INTMAX_MAX INT64_MAX | 
| #define | INTMAX_MIN INT64_MIN | 
| #define | UINTMAX_MAX UINT64_MAX | 
Limits of other integer types | |
|  C++ implementations should define these macros only when __STDC_LIMIT_MACROS is defined before <stdint.h> is included  | |
| #define | PTRDIFF_MAX INT16_MAX | 
| #define | PTRDIFF_MIN INT16_MIN | 
| #define | SIG_ATOMIC_MAX INT8_MAX | 
| #define | SIG_ATOMIC_MIN INT8_MIN | 
| #define | SIZE_MAX (__CONCAT(INT16_MAX, U)) | 
Macros for integer constants | |
|  C++ implementations should define these macros only when __STDC_CONSTANT_MACROS is defined before <stdint.h> is included.These definitions are valid for integer constants without suffix and for macros defined as integer constant without suffix  | |
| #define | INT8_C(value) ((int8_t) value) | 
| #define | UINT8_C(value) ((uint8_t) __CONCAT(value, U)) | 
| #define | INT16_C(value) value | 
| #define | UINT16_C(value) __CONCAT(value, U) | 
| #define | INT32_C(value) __CONCAT(value, L) | 
| #define | UINT32_C(value) __CONCAT(value, UL) | 
| #define | INT64_C(value) __CONCAT(value, LL) | 
| #define | UINT64_C(value) __CONCAT(value, ULL) | 
| #define | INTMAX_C(value) __CONCAT(value, LL) | 
| #define | UINTMAX_C(value) __CONCAT(value, ULL) | 
 #include <stdint.h> 
Use [u]intN_t if you need exactly N bits.
Since these typedefs are mandated by the C99 standard, they are preferred over rolling your own typedefs.
| #define INT16_C | ( | value | ) | value | 
define a constant of type int16_t
| #define INT16_MAX 0x7fff | 
largest positive value an int16_t can hold.
| #define INT16_MIN (-INT16_MAX - 1) | 
smallest negative value an int16_t can hold.
| #define INT32_C | ( | value | ) | __CONCAT(value, L) | 
define a constant of type int32_t
| #define INT32_MAX 0x7fffffffL | 
largest positive value an int32_t can hold.
| #define INT32_MIN (-INT32_MAX - 1L) | 
smallest negative value an int32_t can hold.
| #define INT64_C | ( | value | ) | __CONCAT(value, LL) | 
define a constant of type int64_t
| #define INT64_MAX 0x7fffffffffffffffLL | 
largest positive value an int64_t can hold.
| #define INT64_MIN (-INT64_MAX - 1LL) | 
smallest negative value an int64_t can hold.
| #define INT8_C | ( | value | ) | ((int8_t) value) | 
define a constant of type int8_t
| #define INT8_MAX 0x7f | 
largest positive value an int8_t can hold.
| #define INT8_MIN (-INT8_MAX - 1) | 
smallest negative value an int8_t can hold.
| #define INT_FAST16_MAX INT16_MAX | 
largest positive value an int_fast16_t can hold.
| #define INT_FAST16_MIN INT16_MIN | 
smallest negative value an int_fast16_t can hold.
| #define INT_FAST32_MAX INT32_MAX | 
largest positive value an int_fast32_t can hold.
| #define INT_FAST32_MIN INT32_MIN | 
smallest negative value an int_fast32_t can hold.
| #define INT_FAST64_MAX INT64_MAX | 
largest positive value an int_fast64_t can hold.
| #define INT_FAST64_MIN INT64_MIN | 
smallest negative value an int_fast64_t can hold.
| #define INT_FAST8_MAX INT8_MAX | 
largest positive value an int_fast8_t can hold.
| #define INT_FAST8_MIN INT8_MIN | 
smallest negative value an int_fast8_t can hold.
| #define INT_LEAST16_MAX INT16_MAX | 
largest positive value an int_least16_t can hold.
| #define INT_LEAST16_MIN INT16_MIN | 
smallest negative value an int_least16_t can hold.
| #define INT_LEAST32_MAX INT32_MAX | 
largest positive value an int_least32_t can hold.
| #define INT_LEAST32_MIN INT32_MIN | 
smallest negative value an int_least32_t can hold.
| #define INT_LEAST64_MAX INT64_MAX | 
largest positive value an int_least64_t can hold.
| #define INT_LEAST64_MIN INT64_MIN | 
smallest negative value an int_least64_t can hold.
| #define INT_LEAST8_MAX INT8_MAX | 
largest positive value an int_least8_t can hold.
| #define INT_LEAST8_MIN INT8_MIN | 
smallest negative value an int_least8_t can hold.
| #define INTMAX_C | ( | value | ) | __CONCAT(value, LL) | 
define a constant of type intmax_t
| #define INTMAX_MAX INT64_MAX | 
largest positive value an intmax_t can hold.
| #define INTMAX_MIN INT64_MIN | 
smallest negative value an intmax_t can hold.
| #define INTPTR_MAX INT16_MAX | 
largest positive value an intptr_t can hold.
| #define INTPTR_MIN INT16_MIN | 
smallest negative value an intptr_t can hold.
| #define PTRDIFF_MAX INT16_MAX | 
largest positive value a ptrdiff_t can hold.
| #define PTRDIFF_MIN INT16_MIN | 
smallest negative value a ptrdiff_t can hold.
| #define SIG_ATOMIC_MAX INT8_MAX | 
largest positive value a sig_atomic_t can hold.
| #define SIG_ATOMIC_MIN INT8_MIN | 
smallest negative value a sig_atomic_t can hold.
| #define SIZE_MAX (__CONCAT(INT16_MAX, U)) | 
largest value a size_t can hold.
| #define UINT16_C | ( | value | ) | __CONCAT(value, U) | 
define a constant of type uint16_t
| #define UINT16_MAX (__CONCAT(INT16_MAX, U) * 2U + 1U) | 
largest value an uint16_t can hold.
| #define UINT32_C | ( | value | ) | __CONCAT(value, UL) | 
define a constant of type uint32_t
| #define UINT32_MAX (__CONCAT(INT32_MAX, U) * 2UL + 1UL) | 
largest value an uint32_t can hold.
| #define UINT64_C | ( | value | ) | __CONCAT(value, ULL) | 
define a constant of type uint64_t
| #define UINT64_MAX (__CONCAT(INT64_MAX, U) * 2ULL + 1ULL) | 
largest value an uint64_t can hold.
| #define UINT8_C | ( | value | ) | ((uint8_t) __CONCAT(value, U)) | 
define a constant of type uint8_t
| #define UINT8_MAX (__CONCAT(INT8_MAX, U) * 2U + 1U) | 
largest value an uint8_t can hold.
| #define UINT_FAST16_MAX UINT16_MAX | 
largest value an uint_fast16_t can hold.
| #define UINT_FAST32_MAX UINT32_MAX | 
largest value an uint_fast32_t can hold.
| #define UINT_FAST64_MAX UINT64_MAX | 
largest value an uint_fast64_t can hold.
| #define UINT_FAST8_MAX UINT8_MAX | 
largest value an uint_fast8_t can hold.
| #define UINT_LEAST16_MAX UINT16_MAX | 
largest value an uint_least16_t can hold.
| #define UINT_LEAST32_MAX UINT32_MAX | 
largest value an uint_least32_t can hold.
| #define UINT_LEAST64_MAX UINT64_MAX | 
largest value an uint_least64_t can hold.
| #define UINT_LEAST8_MAX UINT8_MAX | 
largest value an uint_least8_t can hold.
| #define UINTMAX_C | ( | value | ) | __CONCAT(value, ULL) | 
define a constant of type uintmax_t
| #define UINTMAX_MAX UINT64_MAX | 
largest value an uintmax_t can hold.
| #define UINTPTR_MAX UINT16_MAX | 
largest value an uintptr_t can hold.
| typedef signed int int16_t | 
16-bit signed type.
| typedef signed long int int32_t | 
32-bit signed type.
| typedef signed long long int int64_t | 
64-bit signed type.
| typedef signed char int8_t | 
8-bit signed type.
| typedef int16_t int_fast16_t | 
fastest signed int with at least 16 bits.
| typedef int32_t int_fast32_t | 
fastest signed int with at least 32 bits.
| typedef int64_t int_fast64_t | 
fastest signed int with at least 64 bits.
| typedef int8_t int_fast8_t | 
fastest signed int with at least 8 bits.
| typedef int16_t int_least16_t | 
signed int with at least 16 bits.
| typedef int32_t int_least32_t | 
signed int with at least 32 bits.
| typedef int64_t int_least64_t | 
signed int with at least 64 bits.
| typedef int8_t int_least8_t | 
signed int with at least 8 bits.
| typedef unsigned int uint16_t | 
16-bit unsigned type.
| typedef unsigned long int uint32_t | 
32-bit unsigned type.
| typedef unsigned long long int uint64_t | 
64-bit unsigned type.
| typedef unsigned char uint8_t | 
8-bit unsigned type.
| typedef uint16_t uint_fast16_t | 
fastest unsigned int with at least 16 bits.
| typedef uint32_t uint_fast32_t | 
fastest unsigned int with at least 32 bits.
| typedef uint64_t uint_fast64_t | 
fastest unsigned int with at least 64 bits.
| typedef uint8_t uint_fast8_t | 
fastest unsigned int with at least 8 bits.
| typedef uint16_t uint_least16_t | 
unsigned int with at least 16 bits.
| typedef uint32_t uint_least32_t | 
unsigned int with at least 32 bits.
| typedef uint64_t uint_least64_t | 
unsigned int with at least 64 bits.
| typedef uint8_t uint_least8_t | 
unsigned int with at least 8 bits.