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It is very convenient to have operators which return the “minimum” or the “maximum” of two arguments. In GNU C++ (but not in GNU C),

`a``<?`

`b`- is the minimum, returning the smaller of the numeric values
`a`and`b`; `a``>?`

`b`- is the maximum, returning the larger of the numeric values
`a`and`b`.

These operations are not primitive in ordinary C++, since you can use a macro to return the minimum of two things in C++, as in the following example.

#define MIN(X,Y) ((X) < (Y) ? : (X) : (Y))

You might then use ``int min = MIN (i, j);`' to set `min` to
the minimum value of variables `i` and `j`.

However, side effects in `X`

or `Y`

may cause unintended
behavior. For example, `MIN (i++, j++)`

will fail, incrementing
the smaller counter twice. The GNU C `typeof`

extension allows you
to write safe macros that avoid this kind of problem (see Typeof).
However, writing `MIN`

and `MAX`

as macros also forces you to
use function-call notation for a fundamental arithmetic operation.
Using GNU C++ extensions, you can write ``int min = i <? j;`'
instead.

Since `<?`

and `>?`

are built into the compiler, they properly
handle expressions with side-effects; ``int min = i++ <? j++;`'
works correctly.