unordered_multiset::empty

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bool empty() const;

备注

成员函数返回 true 为空控件序列。

示例

 

// std_tr1__unordered_set__unordered_multiset_empty.cpp 
// compile with: /EHsc 
#include <unordered_set> 
#include <iostream> 
 
typedef std::unordered_multiset<char> Myset; 
int main() 
    { 
    Myset c1; 
 
    c1.insert('a'); 
    c1.insert('b'); 
    c1.insert('c'); 
 
// display contents " [c] [b] [a]" 
    for (Myset::const_iterator it = c1.begin(); 
        it != c1.end(); ++it) 
        std::cout << " [" << *it << "]"; 
    std::cout << std::endl; 
 
// clear the container and reinspect 
    c1.clear(); 
    std::cout << "size == " << c1.size() << std::endl; 
    std::cout << "empty() == " << std::boolalpha << c1.empty() << std::endl; 
    std::cout << std::endl; 
 
    c1.insert('d'); 
    c1.insert('e'); 
 
// display contents " [e] [d]" 
    for (Myset::const_iterator it = c1.begin(); 
        it != c1.end(); ++it) 
        std::cout << " [" << *it << "]"; 
    std::cout << std::endl; 
 
    std::cout << "size == " << c1.size() << std::endl; 
    std::cout << "empty() == " << std::boolalpha << c1.empty() << std::endl; 
 
    return (0); 
    } 
 
  

要求

**标题:**unordered_set

命名空间: std

请参见

参考

<unordered_set>

unordered_multiset Class

unordered_multiset::size

其他资源

unordered_set 成员