0x10000000u

0x10000000u is a hexadecimal integer literal used in C and C++ to represent an unsigned value. The suffix u indicates unsigned, so the literal is of an unsigned integer type. On common 32-bit systems, this type is unsigned int.

Numerically, 0x10000000 equals 268,435,456 in decimal. In binary it is a 1 at bit position 28 with all lower bits zero (2^28). In memory terms, this value corresponds to 256 mebibytes (MiB), i.e., 268,435,456 bytes, though the literal itself is simply a numeric constant and not a memory allocation.

Common uses for 0x10000000u include representing a specific constant in bitwise operations, memory sizing, or address calculations. It can function as a bit mask with a single high bit set (useful in flag fields), as a boundary or alignment constant in memory layouts, or as part of a larger expression to scale or offset addresses or sizes. For example, shifting or masking operations may rely on this value to isolate or set the 28th bit.

Portability notes: the exact type of 0x10000000u is determined by the language standard and the platform. With typical 32-bit unsigned int, its type is unsigned int. On platforms with different integer sizes, the compiler may choose unsigned long or another unsigned type to represent the value when necessary. Regardless of type, its numeric value remains 268,435,456.