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As there are various types of 64-bit data models (LLP64/IL32P64, LP64/I32LP64, ILP64, SILP64), what is the standard conforming way of specifying 64-bit unsigned integer literals?
Would specifying the suffix of ULL be sufficient? Or would I end up causing the literal to be interpreted as 128-bit on some data models?
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uint64. A 64-bit unsigned integer. It has a minimum value of 0 and a maximum value of (2^64)-1 (inclusive).
Microsoft C/C++ features support for sized integer types. You can declare 8-, 16-, 32-, or 64-bit integer variables by using the __intN type specifier, where N is 8, 16, 32, or 64.
As a recap, remember that the maximum number stored in a 64 bit register / variable is 2^64 – 1 = 18446744073709551615 (a 20 digit number).
A 64-bit register can hold any of 264 (over 18 quintillion or 1.8×1019) different values. The range of integer values that can be stored in 64 bits depends on the integer representation used.
You should use <cstdint> / <stdint.h>, if you have it. This will give you:
uint64_t is an unsigned integer type which is 64 bits in sizeUINT64_C() is a macro for creating constants of the type uint64_t, by having the macro append the proper suffix.
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