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### 27.2 Maximum and Minimum Values

For each primitive integer type, there is a standard macro defined in limits.h that gives the largest value that type can hold. For instance, for type `int`, the maximum value is `INT_MAX`. On a 32-bit computer, that is equal to 2,147,483,647. The maximum value for `unsigned int` is `UINT_MAX`, which on a 32-bit computer is equal to 4,294,967,295. Likewise, there are `SHRT_MAX`, `LONG_MAX`, and `LLONG_MAX`, and corresponding unsigned limits `USHRT_MAX`, `ULONG_MAX`, and `ULLONG_MAX`.

Since there are three ways to specify a `char` type, there are also three limits: `CHAR_MAX`, `SCHAR_MAX`, and `UCHAR_MAX`.

For each type that is or might be signed, there is another symbol that gives the minimum value it can hold. (Just replace `MAX` with `MIN` in the names listed above.) There is no minimum limit symbol for types specified with `unsigned` because the minimum for them is universally zero.

`INT_MIN` is not the negative of `INT_MAX`. In two’s-complement representation, the most negative number is 1 less than the negative of the most positive number. Thus, `INT_MIN` on a 32-bit computer has the value -2,147,483,648. You can’t actually write the value that way in C, since it would overflow. That’s a good reason to use `INT_MIN` to specify that value. Its definition is written to avoid overflow.