`lexicographical_compare` compares element by element `rng1` against `rng2`. If the element from `rng1` is less than the element from `rng2` then `true` is returned. If the end of `rng1` without reaching the end of `rng2` this also causes the return value to be `true`. The return value is `false` in all other circumstances. The elements are compared using `operator<` in the non-predicate versions of `lexicographical_compare` and using `pred` in the predicate versions.
[heading Definition]
Defined in the header file `boost/range/algorithm/lexicographical_compare.hpp`
[heading Requirements]
[*For the non-predicate versions of lexicographical_compare:]
* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
* `SinglePassRange1`'s value type is a model of the `LessThanComparableConcept`.
* `SinglePassRange2`'s value type is a model of the `LessThanComparableConcept`.
* Let `x` be an object of `SinglePassRange1`'s value type. Let `y` be an obect of `SinglePassRange2`'s value type. `x < y` must be valid. `y < x` must be valid.
[*For the predicate versions of lexicographical_compare:]
* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
* `BinaryPredicate` is a model of the `BinaryPredicateConcept`.
* `SinglePassRange1`'s value type is convertible to `BinaryPredicate`'s first argument type.
* `SinglePassRange2`'s value type is convertible to `BinaryPredicate`'s second argument type.
[heading Complexity]
Linear. At most `2 * min(distance(rng1), distance(rng2))` comparisons.