lexicographical_compare

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##### lexicographical_compare

###### Prototype

    template<
        class SinglePassRange1,
        class SinglePassRange2
        >
    bool lexicographical_compare(const SinglePassRange1& rng1,
                                 const SinglePassRange2& rng2);

    template<
        class SinglePassRange1,
        class SinglePassRange2,
        class BinaryPredicate
        >
    bool lexicographical_compare(const SinglePassRange1& rng1,
                                 const SinglePassRange2& rng2,
                                 BinaryPredicate pred);

###### Description

`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.

###### Definition

Defined in the header file `boost/range/algorithm/lexicographical_compare.hpp`

###### 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 object 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.

###### Complexity

Linear. At most `2 * min(distance(rng1), distance(rng2))` comparisons.