multimap-constructors

// 2018/05/02 15:31:13
// multimap-constructors
#include <iostream>
#include <map>using namespace std;int main(){/** multimap特性以及用法与map完全相同，唯一的差别在于:* 允许重复键值的元素插入容器(使用了RB-Tree的insert_equal函数)*/typedef multimap<int, char, less<int>> M;M m1;m1.insert(M::value_type(2,'B'));m1.insert(M::value_type(3,'C'));m1.insert(M::value_type(1,'A'));m1.insert(M::value_type(1,'a'));M::iterator it = m1.begin();cout << "m1:" << endl;while (it != m1.end()){cout << it->first << "-" << it->second << endl;it++;}// copy constructorM m2(m1);it = m2.begin();cout << "m2:" << endl;while (it != m2.end()){cout << it->first << "-" << it->second << endl;it++;}cout << "m3:" << endl;M m3(m2.begin(), m2.end());it = m3.begin();while (it != m3.end()){cout << it->first << "-" << it->second << endl;it++;}return 0;
}/* OUTPUT:m1:1-A1-a2-B3-Cm2:1-A1-a2-B3-Cm3:1-A1-a2-B3-C */