hash_map::rehash (STL/CLR)
Rebuilds the hash table.
void rehash();
Remarks
The member function rebuilds the hash table, ensuring that hash_map::load_factor (STL/CLR)() <= hash_map::max_load_factor (STL/CLR). Otherwise, the hash table increases in size only as needed after an insertion. (It never automatically decreases in size.) You use it to adjust the size of the hash table.
Example
// cliext_hash_map_rehash.cpp
// compile with: /clr
#include <cliext/hash_map>
typedef cliext::hash_map<wchar_t, int> Myhash_map;
int main()
{
Myhash_map c1 = gcnew Myhash_map;
c1.insert(Myhash_map::make_value(L'a', 1));
c1.insert(Myhash_map::make_value(L'b', 2));
c1.insert(Myhash_map::make_value(L'c', 3));
// display contents " [a 1] [b 2] [c 3]"
for each (Myhash_map::value_type elem in c1)
System::Console::Write(" [{0} {1}]", elem->first, elem->second);
System::Console::WriteLine();
// inspect current parameters
System::Console::WriteLine("bucket_count() = {0}", c1.bucket_count());
System::Console::WriteLine("load_factor() = {0}", c1.load_factor());
System::Console::WriteLine("max_load_factor() = {0}",
c1.max_load_factor());
System::Console::WriteLine();
// change max_load_factor and redisplay
c1.max_load_factor(0.25f);
System::Console::WriteLine("bucket_count() = {0}", c1.bucket_count());
System::Console::WriteLine("load_factor() = {0}", c1.load_factor());
System::Console::WriteLine("max_load_factor() = {0}",
c1.max_load_factor());
System::Console::WriteLine();
// rehash and redisplay
c1.rehash(100);
System::Console::WriteLine("bucket_count() = {0}", c1.bucket_count());
System::Console::WriteLine("load_factor() = {0}", c1.load_factor());
System::Console::WriteLine("max_load_factor() = {0}",
c1.max_load_factor());
return (0);
}
[a 1] [b 2] [c 3] bucket_count() = 16 load_factor() = 0.1875 max_load_factor() = 4 bucket_count() = 16 load_factor() = 0.1875 max_load_factor() = 0.25 bucket_count() = 128 load_factor() = 0.0234375 max_load_factor() = 0.25
Requirements
Header: <cliext/hash_map>
Namespace: cliext
See Also
Reference
hash_map::bucket_count (STL/CLR)