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hash_set::rehash (STL/CLR)

Rebuilds the hash table.

    void rehash();

Remarks

The member function rebuilds the hash table, ensuring that hash_set::load_factor (STL/CLR)() <= hash_set::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_set_rehash.cpp 
// compile with: /clr 
#include <cliext/hash_set> 
 
typedef cliext::hash_set<wchar_t> Myhash_set; 
int main() 
    { 
    Myhash_set c1; 
    c1.insert(L'a'); 
    c1.insert(L'b'); 
    c1.insert(L'c'); 
 
// display initial contents " a b c" 
    for each (wchar_t elem in c1) 
        System::Console::Write(" {0}", elem); 
    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 b c
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_set>

Namespace: cliext

See Also

Concepts

hash_set (STL/CLR)

hash_set::bucket_count (STL/CLR)

hash_set::load_factor (STL/CLR)

hash_set::max_load_factor (STL/CLR)