std::unordered_map - how to “track” max/min key at any time

Question

I have std::unordered_map. I do not want to use other structures like tree or anything else cause latency requirements. But at any time I need t

Answer 1

You can write a wrapper. With that, you get every insertion/deletion and can retain min / max values.

#pragma once

#include 

using std::unordered_map;

class my_unordered_map
{
public:
    void insert(int key, int value)
    {
        _map[key] = value;
        if (_max < value)
            _max = value;
        if (_min> value)
            _min = value;
    }
    int get(int key)
    {
        auto it = _map.find(key);
        if (it != _map.end())
            return it->second;
        return 0; // or some error handling here.
    }
    int getMin()
    {
        return _min;
    }
    int getMax()
    {
        return _max;
    }
    // more functionality here.
private:
    unordered_map _map;
    int _min = 0;
    int _max = 0;
};