c++ map 与multimap关联容器

map

#include <iostream>
#include <string.h>
#include <map>
using namespace std;
int main() {
    pair<int, string> t(9, "Asia");
    //cout << t.first << " " << t.second << endl << endl;
    pair<int, string> sz[4] = {
        pair<int,string>(9,"USA"),
        pair<int,string>(4,"UK"),
        pair<int,string>(5,"China"),
        pair<int,string>(8,"Germany"),
    };

    map<int, string> obM(sz, sz + 4);
    cout<<"size of map: "<<obM.size()<<endl;
    map<int, string>::iterator it = obM.begin();
    while (it != obM.end()) {
        cout << (*it).first << " "<<(*it).second<<endl;
        ++it;
    }

    return 0;
}

map 按关键字大小排序输出

map输出

multimap

#include <iostream>
#include <string.h>
#include <map>
using namespace std;
int main() {
    pair<int, string> t(9, "Asia");
    //cout << t.first << " " << t.second << endl << endl;
    pair<int, string> sz[4] = {
        pair<int,string>(9,"USA"),
        pair<int,string>(4,"UK"),
        pair<int,string>(4,"China"),
        pair<int,string>(4,"Germany"),
    };

    multimap<int, string> obM(sz, sz + 4);
    cout<<"size of map: "<<obM.size()<<endl;
    multimap<int, string>::iterator it = obM.begin();
    while (it != obM.end()) {
        cout << (*it).first << " "<<(*it).second<<endl;
        ++it;
    }
    return 0;
}

multimap 输出

• multimap 允许关键值重复输出类容