multimap::upper_bound
傳回 Iterator 置於與索引鍵大於指定之索引鍵的多重對應的第一個項目。
iterator upper_bound(
const Key& _Key
);
const_iterator upper_bound(
const Key& _Key
) const;
參數
- _Key
引數索引鍵與項目的排序鍵會比較搜尋字串的多個對應的。
傳回值
處理一個項目位置在多重對應的索引鍵大於引數金鑰,或是處理成功最後一個項目的位置在多重對應的 Iterator 則為 const_iterator ,如果遊戲不為索引鍵中找到。
如果的傳回值指派給 const_iterator,無法修改多重對應物件。 如果的傳回值指派給 iterator,可以修改多重對應物件。
範例
// multimap_upper_bound.cpp
// compile with: /EHsc
#include <map>
#include <iostream>
int main( )
{
using namespace std;
multimap <int, int> m1;
multimap <int, int> :: const_iterator m1_AcIter, m1_RcIter;
typedef pair <int, int> Int_Pair;
m1.insert ( Int_Pair ( 1, 10 ) );
m1.insert ( Int_Pair ( 2, 20 ) );
m1.insert ( Int_Pair ( 3, 30 ) );
m1.insert ( Int_Pair ( 3, 40 ) );
m1_RcIter = m1.upper_bound( 1 );
cout << "The 1st element of multimap m1 with "
<< "a key greater than 1 is: "
<< m1_RcIter -> second << "." << endl;
m1_RcIter = m1.upper_bound( 2 );
cout << "The first element of multimap m1 with a key "
<< " greater than 2 is: "
<< m1_RcIter -> second << "." << endl;
// If no match is found for the key, end( ) is returned
m1_RcIter = m1.lower_bound( 4 );
if ( m1_RcIter == m1.end( ) )
cout << "The multimap m1 doesn't have an element "
<< "with a key of 4." << endl;
else
cout << "The element of multimap m1 with a key of 4 is: "
<< m1_RcIter -> second << "." << endl;
// The element at a specific location in the multimap can be
// found using a derefenced iterator addressing the location
m1_AcIter = m1.begin( );
m1_RcIter = m1.upper_bound( m1_AcIter -> first );
cout << "The first element of m1 with a key greater than\n"
<< "that of the initial element of m1 is: "
<< m1_RcIter -> second << "." << endl;
}
需求
標頭:<map>
命名空間: std