However, the value of (ptrdiff_t)((size_t)3-(size_t)4) is positive if ptrdiff_t has at least 17 bits, and size_t only has 16 bits, and negative whenever ptrdiff

However, the value of (ptrdiff_t)((size_t)3-(size_t)4) is positive if ptrdiff_t has at least 17 bits, and size_t only has 16 bits, and negative whenever ptrdiff_t and size_t have the same number of bits.