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### 6.1 Minimum and Maximum Operators in C++

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.