multiset::lower_bound

返回迭代器到多个集的第一个元素与等于或大于指定的键的键。

const_iterator lower_bound(
   const Key& _Key
) const;
iterator lower_bound(
   const Key& _Key
);

参数

• _Key
  参数键与一个元素的排序关键字进行比较从要搜索的多个集的。

返回值

解决一个元素位置在多个集的密钥等于或大于参数键，或者解决成功最后一个元素的位置在多个集的 iterator 或 const_iterator，如果与未作为项中。

示例

// multiset_lower_bound.cpp
// compile with: /EHsc
#include <set>
#include <iostream>

int main( )
{
   using namespace std;   
   multiset <int> ms1;
   multiset <int> :: const_iterator ms1_AcIter, ms1_RcIter;
   
   ms1.insert( 10 );
   ms1.insert( 20 );
   ms1.insert( 30 );

   ms1_RcIter = ms1.lower_bound( 20 );
   cout << "The element of multiset ms1 with a key of 20 is: "
        << *ms1_RcIter << "." << endl;

   ms1_RcIter = ms1.lower_bound( 40 );

   // If no match is found for the key, end( ) is returned
   if ( ms1_RcIter == ms1.end( ) )
      cout << "The multiset ms1 doesn't have an element "
           << "with a key of 40." << endl;
   else
      cout << "The element of multiset ms1 with a key of 40 is: "
           << *ms1_RcIter << "." << endl;

   // The element at a specific ___location in the multiset can be 
   // found using a derefenced iterator addressing the ___location
   ms1_AcIter = ms1.end( );
   ms1_AcIter--;
   ms1_RcIter = ms1.lower_bound( *ms1_AcIter );
   cout << "The element of ms1 with a key matching "
        << "that of the last element is: "
        << *ms1_RcIter << "." << endl;
}

要求

标头: <set>

命名空间: std

请参见

参考

multiset Class

标准模板库