Question

I am using std::unordered_map and was trying to get the memory consumption so I did the following:

#include <iostream>
#include <unordered_map>

using namespace std;

int main(){
    unordered_map<int, int> map;
    map[21] = 12;

    cout << map.size() << endl << map.max_size() << endl;

    return 0;
}

to which the result is:

1
1152921504606846975

the first one is correct, what the heck is the second one?!

Answer 1

map.max_size() 

Returns the maximum potential size the container can reach due to system or library implementation limitations.

---

map.size() 

Returns the number of elements in the container.