map的增加元素，删除元素，查找元素操作

#include<map>
#include<iostream>

using namespace std;

int main()
{
    map<string, string> a; //定义一个map
    map<string, string>::iterator iter; 
    cout << "-----------增加元素" << endl;
    a["cat"] = "猫";
    // a["dog"] = "gou";
    a.insert(pair<string, string>("dog", "狗"));
    a.insert(pair<string, string>("fish", "鱼"));
    cout << a["cat"] << endl;
    cout << a["dog"] << endl;
    cout << a["fish"] << endl;
    cout << "------------删除元素" << endl;
    iter = a.find("fish");
    a.erase(iter); // 使用迭代器删除 
    int n = a.erase("dog"); // 使用key删除 
    cout << "是否删除dog成功？:" << n << endl;
    // a.erase(a.begin(), a.end()); // 全部删除， == a.clear() 
    // a.clear(); // 全部删除 
    
    cout << "-------------查找元素" << endl;
    iter = a.find("cat");
    if(iter != a.end())
    {
        cout << "I find it" << endl;
        cout << iter->first << endl;
        cout << iter->second << endl;
    }
    else
    {
        cout << "Do not Find" << endl;
    }
    return 0;
}