swap 函式 (unordered_map)
交換兩個容器的內容。
template<class Key, class Ty, class Hash, class Pred, class Alloc>
void swap(
unordered_map <Key, Ty, Hash, Pred, Alloc>& left,
unordered_map <Key, Ty, Hash, Pred, Alloc>& right);
參數
Key
金鑰類型。Ty
對應的類型。Hash
雜湊函式物件類型。Pred
相等比較函式物件類型。Alloc
配置器類別。left
交換第一個容器。right
交換的第二個容器。
備註
樣板函式執行 left.unordered_map::swap(right)。
範例
// std_tr1__unordered_map__u_m_swap.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;
Mymap c2;
c2.insert(Mymap::value_type('d', 4));
c2.insert(Mymap::value_type('e', 5));
c2.insert(Mymap::value_type('f', 6));
c1.swap(c2);
// display contents " [f 6] [e 5] [d 4]"
for (Mymap::const_iterator it = c1.begin();
it != c1.end(); ++it)
std::cout << " [" << it->first << ", " << it->second << "]";
std::cout << std::endl;
swap(c1, c2);
// 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;
return (0);
}
需求
標頭： <unordered_map>
命名空間: std