Exit Zen
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Returns the index of the bucket which would contain `k`.
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22
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`local_iterator begin(size_type n)`
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23
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1.6+|Return begin and end iterators for bucket `n`.
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24
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`local_iterator end(size_type n)`
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25
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`const_local_iterator begin(size_type n) const`
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26
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`const_local_iterator end(size_type n) const`
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27
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`const_local_iterator cbegin(size_type n) const`
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28
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`const_local_iterator cend(size_type n) const`
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29
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Controlling the Number of Buckets
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30
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As more elements are added to an unordered associative container, the number of collisions will increase causing performance to degrade. To combat this the containers increase the bucket count as elements are inserted. You can also tell the container to change the bucket count (if required) by calling `rehash`.
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31
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The standard leaves a lot of freedom to the implementer to decide how the number of buckets is chosen, but it does make some requirements based on the container's _load factor_, the number of elements divided by the number of buckets. Containers also have a _maximum load factor_ which they should try to keep the load factor below.
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32
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You can't control the bucket count directly but there are two ways to influence it:
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33
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Specify the minimum number of buckets when constructing a container or when calling `rehash`.
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34
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Suggest a maximum load factor by calling `max_load_factor`.
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35
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`max_load_factor` doesn't let you set the maximum load factor yourself, it just lets you give a _hint_. And even then, the standard doesn't actually require the container to pay much attention to this value. The only time the load factor is _required_ to be less than the maximum is following a call to `rehash`. But most implementations will try to keep the number of elements below the max load factor, and set the maximum load factor to be the same as or close to the hint - unless your hint is unreasonably small or large.
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:111
:111
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2+^h| *All containers* h|*Method* h|*Description*
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37
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`X(size_type n)`
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38
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Construct an empty container with at least `n` buckets (`X` is the container type).
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39
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`X(InputIterator i, InputIterator j, size_type n)`
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40
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Construct an empty container with at least `n` buckets and insert elements from the range `[i, j)` (`X` is the container type).
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