unordered_multiset::difference_type

项目
06/09/2015

两个元素间的带符号距离的类型。

typedef T3 difference_type;

备注

带符号整数类型描述可以表示任何两个元素间的差异。地址控件序列的对象。它介绍此处，实现定义类型 T3的同义词。

示例

// std_tr1__unordered_set__unordered_multiset_difference_type.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; 
 
// compute positive difference 
    Myset::difference_type diff = 0; 
    for (Myset::const_iterator it = c1.begin(); 
        it != c1.end(); ++it) 
        ++diff; 
    std::cout << "end()-begin() == " << diff << std::endl; 
 
// compute negative difference 
    diff = 0; 
    for (Myset::const_iterator it = c1.end(); 
        it != c1.begin(); --it) 
        --diff; 
    std::cout << "begin()-end() == " << diff << std::endl; 
 
    return (0); 
    }