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<array> operators

The <array> header includes these array non-member comparison template functions.

operator!=

Array comparison, not equal.

template <class Ty, std::size_t N>
bool operator!=(
    const array<Ty, N>& left,
    const array<Ty, N>& right);

Parameters

Ty
The type of an element.

N
The size of the array.

left
Left container to compare.

right
Right container to compare.

Remarks

The template function returns !(left == right).

Example

// std__array__operator_ne.cpp
// compile with: /EHsc
#include <array>
#include <iostream>

typedef std::array<int, 4> Myarray;
int main()
    {
    Myarray c0 = {0, 1, 2, 3};

// display contents " 0 1 2 3"
    for (Myarray::const_iterator it = c0.begin();
        it != c0.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

    Myarray c1 = {4, 5, 6, 7};

// display contents " 4 5 6 7"
    for (Myarray::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

// display results of comparisons
    std::cout << std::boolalpha << " " << (c0 != c0);
    std::cout << std::endl;
    std::cout << std::boolalpha << " " << (c0 != c1);
    std::cout << std::endl;

    return (0);
    }

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false
true

operator<

Array comparison, less than.

template <class Ty, std::size_t N>
bool operator<(
    const array<Ty, N>& left,
    const array<Ty, N>& right);

Parameters

Ty
The type of an element.

N
The size of the array.

left
Left container to compare.

right
Right container to compare.

Remarks

The template function overloads operator< to compare two objects of class template array. The function returns lexicographical_compare(left.begin(), left.end(), right.begin()).

Example

// std__array__operator_lt.cpp
// compile with: /EHsc
#include <array>
#include <iostream>

typedef std::array<int, 4> Myarray;
int main()
    {
    Myarray c0 = {0, 1, 2, 3};

// display contents " 0 1 2 3"
    for (Myarray::const_iterator it = c0.begin();
        it != c0.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

    Myarray c1 = {4, 5, 6, 7};

// display contents " 4 5 6 7"
    for (Myarray::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

// display results of comparisons
    std::cout << std::boolalpha << " " << (c0 < c0);
    std::cout << std::endl;
    std::cout << std::boolalpha << " " << (c0 < c1);
    std::cout << std::endl;

    return (0);
    }

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false
true

operator<=

Array comparison, less than or equal.

template <class Ty, std::size_t N>
bool operator<=(
    const array<Ty, N>& left,
    const array<Ty, N>& right);

Parameters

Ty
The type of an element.

N
The size of the array.

left
Left container to compare.

right
Right container to compare.

Remarks

The template function returns !(right < left).

Example

// std__array__operator_le.cpp
// compile with: /EHsc
#include <array>
#include <iostream>

typedef std::array<int, 4> Myarray;
int main()
    {
    Myarray c0 = {0, 1, 2, 3};

// display contents " 0 1 2 3"
    for (Myarray::const_iterator it = c0.begin();
        it != c0.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

    Myarray c1 = {4, 5, 6, 7};

// display contents " 4 5 6 7"
    for (Myarray::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

// display results of comparisons
    std::cout << std::boolalpha << " " << (c0 <= c0);
    std::cout << std::endl;
    std::cout << std::boolalpha << " " << (c1 <= c0);
    std::cout << std::endl;

    return (0);
    }

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true
false

operator==

Array comparison, equal.

template <class Ty, std::size_t N>
bool operator==(
    const array<Ty, N>& left,
    const array<Ty, N>& right);

Parameters

Ty
The type of an element.

N
The size of the array.

left
Left container to compare.

right
Right container to compare.

Remarks

The template function overloads operator== to compare two objects of class template array. The function returns equal(left.begin(), left.end(), right.begin()).

Example

// std__array__operator_eq.cpp
// compile with: /EHsc
#include <array>
#include <iostream>

typedef std::array<int, 4> Myarray;
int main()
    {
    Myarray c0 = {0, 1, 2, 3};

// display contents " 0 1 2 3"
    for (Myarray::const_iterator it = c0.begin();
        it != c0.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

    Myarray c1 = {4, 5, 6, 7};

// display contents " 4 5 6 7"
    for (Myarray::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

// display results of comparisons
    std::cout << std::boolalpha << " " << (c0 == c0);
    std::cout << std::endl;
    std::cout << std::boolalpha << " " << (c0 == c1);
    std::cout << std::endl;

    return (0);
    }

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true
false

operator>

Array comparison, greater than.

template <class Ty, std::size_t N>
bool operator>(
    const array<Ty, N>& left,
    const array<Ty, N>& right);

Parameters

Ty
The type of an element.

N
The size of the array.

left
Left container to compare.

right
Right container to compare.

Remarks

The template function returns (right < left).

Example

// std__array__operator_gt.cpp
// compile with: /EHsc
#include <array>
#include <iostream>

typedef std::array<int, 4> Myarray;
int main()
    {
    Myarray c0 = {0, 1, 2, 3};

// display contents " 0 1 2 3"
    for (Myarray::const_iterator it = c0.begin();
        it != c0.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

    Myarray c1 = {4, 5, 6, 7};

// display contents " 4 5 6 7"
    for (Myarray::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

// display results of comparisons
    std::cout << std::boolalpha << " " << (c0 > c0);
    std::cout << std::endl;
    std::cout << std::boolalpha << " " << (c1 > c0);
    std::cout << std::endl;

    return (0);
    }

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false
true

operator>=

Array comparison, greater than or equal.

template <class Ty, std::size_t N>
bool operator>=(
    const array<Ty, N>& left,
    const array<Ty, N>& right);

Parameters

Ty
The type of an element.

N
The size of the array.

left
Left container to compare.

right
Right container to compare.

Remarks

The template function returns !(left < right).

Example

// std__array__operator_ge.cpp
// compile with: /EHsc
#include <array>
#include <iostream>

typedef std::array<int, 4> Myarray;
int main()
    {
    Myarray c0 = {0, 1, 2, 3};

// display contents " 0 1 2 3"
    for (Myarray::const_iterator it = c0.begin();
        it != c0.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

    Myarray c1 = {4, 5, 6, 7};

// display contents " 4 5 6 7"
    for (Myarray::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " " << *it;
    std::cout << std::endl;

// display results of comparisons
    std::cout << std::boolalpha << " " << (c0 >= c0);
    std::cout << std::endl;
    std::cout << std::boolalpha << " " << (c0 >= c1);
    std::cout << std::endl;

    return (0);
    }

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4 5 6 7
true
false

See also

<array>

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