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Returns the key equivalence comparison predicate used by the unordered_multimap container.
The key equivalence comparison is a predicate that takes two arguments of the key type and returns a bool value indicating whether they are to be considered equivalent. It is adopted by the container on construction (see unordered_multimap's constructor for more info). By default, it is equal_to<key_type>, which returns the same as applying the equal-to operator (==) to the arguments.
Member type key_equal is the type of the key equality comparison predicate used by the container, defined in unordered_multimap as an alias of its fourth template parameter (Pred).
Output:
Reference
C library:
- <cassert> (assert.h)
- <cctype> (ctype.h)
- <cerrno> (errno.h)
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<cfenv> (fenv.h)C++11
- <cfloat> (float.h)
-
<cinttypes> (inttypes.h)C++11
- <ciso646> (iso646.h)
- <climits> (limits.h)
- <clocale> (locale.h)
- <cmath> (math.h)
- <csetjmp> (setjmp.h)
- <csignal> (signal.h)
- <cstdarg> (stdarg.h)
-
<cstdbool> (stdbool.h)C++11
- <cstddef> (stddef.h)
-
<cstdint> (stdint.h)C++11
- <cstdio> (stdio.h)
- <cstdlib> (stdlib.h)
- <cstring> (string.h)
-
<ctgmath> (tgmath.h)C++11
- <ctime> (time.h)
-
<cuchar> (uchar.h)C++11
- <cwchar> (wchar.h)
- <cwctype> (wctype.h)
Containers:
-
<array>C++11
- <deque>
-
<forward_list>C++11
- <list>
- <map>
- <queue>
- <set>
- <stack>
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<unordered_map>C++11
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<unordered_set>C++11
- <vector>
-
Input/Output:
Multi-threading:
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<atomic>C++11
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<condition_variable>C++11
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<future>C++11
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<mutex>C++11
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<thread>C++11
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Other:
- <algorithm>
- <bitset>
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<chrono>C++11
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<codecvt>C++11
- <complex>
- <exception>
- <functional>
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<initializer_list>C++11
- <iterator>
- <limits>
- <locale>
- <memory>
- <new>
- <numeric>
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<random>C++11
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<ratio>C++11
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<regex>C++11
- <stdexcept>
- <string>
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<system_error>C++11
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<tuple>C++11
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<type_traits>C++11
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<typeindex>C++11
- <typeinfo>
- <utility>
- <valarray>
<unordered_map>
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unordered_mapC++11
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unordered_multimapC++11
unordered_multimap
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unordered_multimap::~unordered_multimapC++11
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unordered_multimap::unordered_multimapC++11
member functions
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unordered_multimap::beginC++11
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unordered_multimap::bucketC++11
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unordered_multimap::bucket_countC++11
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unordered_multimap::bucket_sizeC++11
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unordered_multimap::cbeginC++11
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unordered_multimap::cendC++11
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unordered_multimap::clearC++11
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unordered_multimap::countC++11
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unordered_multimap::emplaceC++11
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unordered_multimap::emplace_hintC++11
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unordered_multimap::emptyC++11
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unordered_multimap::endC++11
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unordered_multimap::equal_rangeC++11
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unordered_multimap::eraseC++11
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unordered_multimap::findC++11
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unordered_multimap::get_allocatorC++11
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unordered_multimap::hash_functionC++11
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unordered_multimap::insertC++11
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unordered_multimap::key_eqC++11
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unordered_multimap::load_factorC++11
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unordered_multimap::max_bucket_countC++11
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unordered_multimap::max_load_factorC++11
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unordered_multimap::max_sizeC++11
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unordered_multimap::operator=C++11
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unordered_multimap::rehashC++11
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unordered_multimap::reserveC++11
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unordered_multimap::sizeC++11
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unordered_multimap::swapC++11
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non-member overloads
public member type
<unordered_map>
std::unordered_multimap::key_eq
key_equal key_eq() const;
Get key equivalence predicate
The key equivalence comparison is a predicate that takes two arguments of the key type and returns a bool value indicating whether they are to be considered equivalent. It is adopted by the container on construction (see unordered_multimap's constructor for more info). By default, it is equal_to<key_type>, which returns the same as applying the equal-to operator (==) to the arguments.
Parameters
noneReturn Value
The key equality comparison object.Member type key_equal is the type of the key equality comparison predicate used by the container, defined in unordered_multimap as an alias of its fourth template parameter (Pred).
Example
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Output:
myumm.key_eq() is case sensitive |
Complexity
Constant.Iterator validity
No changes.See also
- unordered_multimap::hash_function
- Get hash function (public member type)
- unordered_multimap::get_allocator
- Get allocator (public member function)
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