Note
Access to this page requires authorization. You can try signing in or changing directories.
Access to this page requires authorization. You can try changing directories.
Rebuilds the hash table.
void rehash(size_type nbuckets);
Parameters
- nbuckets
The requested number of buckets.
Remarks
The member function alters the number of buckets to be at least nbuckets and rebuilds the hash table as needed.
Example
// std_tr1__unordered_set__unordered_multiset_rehash.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;
// inspect current parameters
std::cout << "bucket_count() == " << c1.bucket_count() << std::endl;
std::cout << "load_factor() == " << c1.load_factor() << std::endl;
std::cout << "max_load_factor() == " << c1.max_load_factor() << std::endl;
std::cout << std::endl;
// change max_load_factor and redisplay
c1.max_load_factor(0.10f);
std::cout << "bucket_count() == " << c1.bucket_count() << std::endl;
std::cout << "load_factor() == " << c1.load_factor() << std::endl;
std::cout << "max_load_factor() == " << c1.max_load_factor() << std::endl;
std::cout << std::endl;
// rehash and redisplay
c1.rehash(100);
std::cout << "bucket_count() == " << c1.bucket_count() << std::endl;
std::cout << "load_factor() == " << c1.load_factor() << std::endl;
std::cout << "max_load_factor() == " << c1.max_load_factor() << std::endl;
return (0);
}
[c] [b] [a] bucket_count() == 8 load_factor() == 0.375 max_load_factor() == 4 bucket_count() == 8 load_factor() == 0.375 max_load_factor() == 0.1 bucket_count() == 128 load_factor() == 0.0234375 max_load_factor() == 0.1
Requirements
Header: <unordered_set>
Namespace: std