unordered_map::bucket
Gets the bucket number for a key value.
size_type bucket(const Key& keyval) const;
Parameters
- keyval
The key value to map.
Remarks
The member function returns the bucket number currently corresponding to the key value keyval.
Example
// std_tr1__unordered_map__unordered_map_bucket.cpp
// compile with: /EHsc
#include <unordered_map>
#include <iostream>
typedef std::unordered_map<char, int> Mymap;
int main()
{
Mymap c1;
c1.insert(Mymap::value_type('a', 1));
c1.insert(Mymap::value_type('b', 2));
c1.insert(Mymap::value_type('c', 3));
// display contents " [c 3] [b 2] [a 1]"
for (Mymap::const_iterator it = c1.begin();
it != c1.end(); ++it)
std::cout << " [" << it->first << ", " << it->second << "]";
std::cout << std::endl;
// display buckets for keys
Mymap::size_type bs = c1.bucket('a');
std::cout << "bucket('a') == " << bs << std::endl;
std::cout << "bucket_size(" << bs << ") == " << c1.bucket_size(bs)
<< std::endl;
return (0);
}
[c, 3] [b, 2] [a, 1]
bucket('a') == 7
bucket_size(7) == 1
Requirements
Header: <unordered_map>
Namespace: std