运行如下C++代码：

#include <iostream>
#include <map>
using namespace std;
int main() {
    map<int, string> m;
    m.insert(make_pair(2, "apple"));
    m[1] = "banana";
    m.insert({3, "cherry"});
    m[2] = "date";
    for (auto &p : m) {
        cout << p.first << ":" << p.second << " ";
    }
    return 0;
}