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<unordered_set> functions

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swap (unordered_set)

Swaps the contents of two containers.

template <class Key, class Hash, class Pred, class Alloc>
void swap(
   unordered_set <Key, Hash, Pred, Alloc>& left,
   unordered_set <Key, Hash, Pred, Alloc>& right);

Parameters

Key
The key type.

Hash
The hash function object type.

Pred
The equality comparison function object type.

Alloc
The allocator class.

left
The first container to swap.

right
The second container to swap.

Remarks

The template function executes left.unordered_set::swap(right).

Example

#include <unordered_set>
#include <iostream>

typedef std::unordered_set<char> Myset;
int main()
{
Myset c1;

c1.insert('a');
c1.insert('b');
c1.insert('c');

// display contents " [c] [b] [a]"
for (Myset::const_iterator it = c1.begin();
it != c1.end(); ++it)
std::cout << " [" << *it << "]";
std::cout << std::endl;

Myset c2;

c2.insert('d');
c2.insert('e');
c2.insert('f');

c1.swap(c2);

// display contents " [f] [e] [d]"
for (Myset::const_iterator it = c1.begin();
it != c1.end(); ++it)
std::cout << " [" << *it << "]";
std::cout << std::endl;

swap(c1, c2);

// display contents " [c] [b] [a]"
for (Myset::const_iterator it = c1.begin();
it != c1.end(); ++it)
std::cout << " [" << *it << "]";
std::cout << std::endl;

return (0);
}

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swap (unordered_multiset)

Swaps the contents of two containers.

template <class Key, class Hash, class Pred, class Alloc>
void swap(
   unordered_multiset <Key, Hash, Pred, Alloc>& left,
   unordered_multiset <Key, Hash, Pred, Alloc>& right);

Parameters

Key
The key type.

Hash
The hash function object type.

Pred
The equality comparison function object type.

Alloc
The allocator class.

left
The first container to swap.

right
The second container to swap.

Remarks

The template function executes left.unordered_multiset::swap(right).

Example

// std__unordered_set__u_ms_swap.cpp
// compile with: /EHsc
#include <unordered_set>
#include <iostream>

typedef std::unordered_multiset<char> Myset;
int main()
{
    Myset c1;

    c1.insert('a');
    c1.insert('b');
    c1.insert('c');

    // display contents " [c] [b] [a]"
    for (Myset::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " [" << *it << "]";
    std::cout << std::endl;

    Myset c2;

    c2.insert('d');
    c2.insert('e');
    c2.insert('f');

    c1.swap(c2);

    // display contents " [f] [e] [d]"
    for (Myset::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " [" << *it << "]";
    std::cout << std::endl;

    swap(c1, c2);

    // display contents " [c] [b] [a]"
    for (Myset::const_iterator it = c1.begin();
        it != c1.end(); ++it)
        std::cout << " [" << *it << "]";
    std::cout << std::endl;

    return (0);
}

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