map::map

构造为空或属于某其他映射全部或部分的副本的映射。

map( );
explicit map(
   const Traits& _Comp
);
map(
   const Traits& _Comp,
   const Allocator& _Al
);
map(
   const map& _Right
);
template<class InputIterator>
   map(
      InputIterator _First,
      InputIterator _Last
   );
template<class InputIterator>
   map(
      InputIterator _First,
      InputIterator _Last,
      const Traits& _Comp
   );
template<class InputIterator>
   map(
      InputIterator _First,
      InputIterator _Last,
      const Traits& _Comp,
      const Allocator& _Al
   );
map(
   map&& _Right
);

参数

备注

所有构造函数存储的分配器对象的类型管理映射的内存存储，并且可以通过调用 get_allocator之后返回。分配器参数在所使用的选件类声明和预处理器宏通常忽略替换替换分配器。

所有构造函数初始化它们的映射。

所有构造函数存储用于建立映射的键中一个命令，并可通过调用 key_comp后返回类型特征的函数对象。

指定null的初始映射，第二个参数指定比较函数(_Comp)的类型用于建立元素和第三的顺序显式指定分配器类型(_Al)的前三个构造函数是使用。关键字 explicit 禁止某些类型的自动类型转换。

第四个构造函数指定映射 _Right的副本。

接下来的三个构造函数复制范围[_First，_Last)的映射随着在指定选件类 Traits 和分配器的比较函数的类型的显式的增加。

最后一个构造函数由移动的 _Right指定映射的副本。

示例

// map_map.cpp
// compile with: /EHsc
#include <map>
#include <iostream>

int main( )
{
   using namespace std;
   typedef pair <int, int> Int_Pair;
   map <int, int>::iterator m1_Iter, m3_Iter, m4_Iter, m5_Iter, m6_Iter, m7_Iter;
   map <int, int, greater<int> >::iterator m2_Iter;

   // Create an empty map m0 of key type integer
   map <int, int> m0;

   // Create an empty map m1 with the key comparison
   // function of less than, then insert 4 elements
   map <int, int, less<int> > m1;
   m1.insert( Int_Pair( 1, 10 ) );
   m1.insert( Int_Pair( 2, 20 ) );
   m1.insert( Int_Pair( 3, 30 ) );
   m1.insert( Int_Pair( 4, 40 ) );

   // Create an empty map m2 with the key comparison
   // function of geater than, then insert 2 elements
   map <int, int, greater<int> > m2;
   m2.insert( Int_Pair( 1, 10 ) );
   m2.insert( Int_Pair( 2, 20 ) );

   // Create a map m3 with the 
   // allocator of map m1
   map <int, int>::allocator_type m1_Alloc;
   m1_Alloc = m1.get_allocator( );
   map <int, int> m3( less<int>( ), m1_Alloc );
   m3.insert( Int_Pair( 3, 30 ) );

   // Create a copy, map m4, of map m1
   map <int, int> m4( m1 );

   // Create a map m5 by copying the range m1[_First, _Last)
   map <int, int>::const_iterator m1_bcIter, m1_ecIter;
   m1_bcIter = m1.begin( );
   m1_ecIter = m1.begin( );
   m1_ecIter++;
   m1_ecIter++;
   map <int, int> m5(m1_bcIter, m1_ecIter);

   // Create a map m6 by copying the range m4[_First, _Last)
   // and with the allocator of map m2
   map <int, int>::allocator_type m2_Alloc;
   m2_Alloc = m2.get_allocator( );
   map <int, int> m6( m4.begin( ), ++m4.begin( ), less<int>( ), m2_Alloc);

   cout << "m1 =";
   for ( m1_Iter = m1.begin( ); m1_Iter != m1.end( ); m1_Iter++ )
      cout << " " << m1_Iter -> second;
   cout << endl;
   
   cout << "m2 =";
   for ( m2_Iter = m2.begin( ); m2_Iter != m2.end( ); m2_Iter++ )
      cout << " " << m2_Iter -> second;
   cout << endl;

   cout << "m3 =";
   for ( m3_Iter = m3.begin( ); m3_Iter != m3.end( ); m3_Iter++ )
      cout << " " << m3_Iter -> second;
   cout << endl;

   cout << "m4 =";
   for ( m4_Iter = m4.begin( ); m4_Iter != m4.end( ); m4_Iter++ )
      cout << " " << m4_Iter -> second;
   cout << endl;

   cout << "m5 =";
   for ( m5_Iter = m5.begin( ); m5_Iter != m5.end( ); m5_Iter++ )
      cout << " " << m5_Iter -> second;
   cout << endl;

   cout << "m6 =";
   for ( m6_Iter = m6.begin( ); m6_Iter != m6.end( ); m6_Iter++ )
      cout << " " << m6_Iter -> second;
   cout << endl;

   // Create a map m7 by moving m5
   cout << "m7 =";
   map<int, int> m7(move(m5));
   for ( m7_Iter = m7.begin( ); m7_Iter != m7.end( ); m7_Iter++ )
      cout << " " << m7_Iter -> second;
   cout << endl;
}

Output

m1 = 10 20 30 40
m2 = 20 10
m3 = 30
m4 = 10 20 30 40
m5 = 10 20
m6 = 10
m7 = 10 20

要求

标头: <map>

命名空间: std

请参见

参考

map Class

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