C++ equivalent of Python dictionaries

Question

I\'m currently making a tic-tac-toe program with AI and i\'m having a bit of a trouble translating this line of code (python) :

RANKS = dict([(4,3),                      


        

Answer 1

The closest match in C++ would be an std::unordered_map. This is a hash table mapping int keys to int values.

#include 


std::unordered_map RANKS = {
        { 4, 3 },
        { 0, 2 }, { 2, 2 }, { 6, 2 }, { 8, 2 },
        { 1, 1 }, { 3, 1 }, { 5, 1 }, { 7, 1 }
};

You can access elements using operator[], for example

std::cout << RANKS[0] << std::endl; // prints "2"

Note that the C++ standard library also has the std::map class template, which allows you to create a similar but ordered look-up table std::map, with logarithmic look-up and insertion complexity. But python dicts are hash tables, so unordered_map is a closer match in terms of behaviour.