hash_set::difference_type

참고

이 API는 사용되지 않습니다.unordered_set 클래스를 대신 사용하는 것이 좋습니다.

A signed integer type that can be used to represent the number of elements of a hash_set in a range between elements pointed to by iterators.

typedef list<typename Traits::value_type, typename Traits::allocator_type>::difference_type difference_type;

설명

The difference_type is the type returned when subtracting or incrementing through iterators of the container. The difference_type is typically used to represent the number of elements in the range [_First, _Last) between the iterators _First and _Last, includes the element pointed to by _First and the range of elements up to, but not including, the element pointed to by _Last.

Note that although difference_type is available for all iterators that satisfy the requirements of an input iterator, which includes the class of bidirectional iterators supported by reversible containers such as set, subtraction between iterators is only supported by random-access iterators provided by a random access container, such as vector or deque.

Visual C++.NET 2003에서, <hash_map> 및 <hash_set> 헤더 파일의 멤버는 더 이상 std 네임스페이스에 존재하지 않습니다. 대신 stdext 네임스페이스로 이동되었습니다. 자세한 내용은 stdext 네임스페이스를 참조하십시오.

예제

// hash_set_diff_type.cpp
// compile with: /EHsc
#include <iostream>
#include <hash_set>
#include <algorithm>

int main( )
{
   using namespace std;
   using namespace stdext;

   hash_set <int> hs1;
   hash_set <int>::iterator hs1_Iter, hs1_bIter, hs1_eIter;

   hs1.insert( 20 );
   hs1.insert( 10 );
   hs1.insert( 20 );   // Won't insert as hash_set elements are unique

   hs1_bIter = hs1.begin( );
   hs1_eIter = hs1.end( );

   hash_set <int>::difference_type   df_typ5, df_typ10, df_typ20;

   df_typ5 = count( hs1_bIter, hs1_eIter, 5 );
   df_typ10 = count( hs1_bIter, hs1_eIter, 10 );
   df_typ20 = count( hs1_bIter, hs1_eIter, 20 );

   // The keys, and hence the elements, of a hash_set are unique,
   // so there is at most one of a given value
   cout << "The number '5' occurs " << df_typ5
        << " times in hash_set hs1.\n";
   cout << "The number '10' occurs " << df_typ10
        << " times in hash_set hs1.\n";
   cout << "The number '20' occurs " << df_typ20
        << " times in hash_set hs1.\n";

   // Count the number of elements in a hash_set
   hash_set <int>::difference_type  df_count = 0;
   hs1_Iter = hs1.begin( );
   while ( hs1_Iter != hs1_eIter)
   {
      df_count++;
      hs1_Iter++;
   }

   cout << "The number of elements in the hash_set hs1 is: " 
        << df_count << "." << endl;
}

요구 사항

헤더: <hash_set>

네임스페이스: stdext

참고 항목

참조

hash_set 클래스

표준 템플릿 라이브러리