C++ map()和pair()用法

#include <map> #include <iostream>using namespace std;int main( ){map<int, int> m1;map<int, int>::iterator m1_Iter;//两种不同的插入方式,并用iterator迭代器来遍历打印.m1[0] = 10;m1[1] = 20;m1.insert(pair<int, int>(2, 20));m1.insert(pair<int, int>(3, 40));cout << "The original map m1 is:"<<endl;for(m1_Iter = m1.begin(); m1_Iter != m1.end(); m1_Iter++ )cout << m1_Iter->first<<" "<<m1_Iter->second<<endl;cout << endl;map<string, int> m2;map<string, int>::iterator m2_Iter;m2[string("张三")] = 1;m2[string("李四")] = 2;m2.insert(pair<string, int>(string("王朝"), 3));m2.insert(pair<string, int>(string("马汉"), 4));for(m2_Iter = m2.begin(); m2_Iter != m2.end(); m2_Iter++ )cout << m2_Iter->first<<" "<< m2_Iter->second<<endl;cout << endl;map<string, string> m3;map<string, string>::iterator m3_Iter;m3[string("张三")] = string("100");m3[string("李四")] = string("200");m3.insert(pair<string, string>(string("王朝"), string("300")));m3.insert(pair<string, string>(string("马汉"), string("400")));for(m3_Iter = m3.begin(); m3_Iter != m3.end(); m3_Iter++ )cout << m3_Iter->first<<" "<< m3_Iter->second<<endl;}