初始化靜態2D數組

Question

下面的代碼：

enum Type {Prince, Princess, King, Queen, NumTypes};
enum Country {England, Belgium, Netherlands, NumCountries};

class Factory {
    static const std::array<std::array<int, NumTypes>, NumCountries> probabilities;
    static std::array<std::array<int, NumTypes>, NumCountries> initializeProbabilities() {
        std::array<std::array<int, NumTypes>, NumCountries> p;
        p[England] =     {29, 60, 80, 100};
        p[Belgium] =     {31, 66, 81, 100};
        p[Netherlands] = {25, 45, 90, 100};
      return p;
    }
};
const std::array<std::array<int, NumTypes>, NumCountries> Factory::probabilities = initializeProbabilities();

如果我曾經更改enum Country中元素的順序是安全的，但是將來對enum Type元素進行任何重新排序都不安全。 避免一個接一個地初始化所有12個元素的最佳方法是什么？

Answer 1

為了避免對訂單的依賴性，您應該編寫如下內容：

p[England][Prince]=29;
p[England][Princess]=60;
p[England][King]=80;
p[England][Queen]=100;

p[Belgium][Prince]=31;
p[Belgium][Princess]=66;
p[Belgium][King]=81;
p[Belgium][Queen]=100;

Answer 2

這是Brian提出的解決方案（我想這就是他的意思）。 這可能是解決所描述問題的最佳方法嗎？

enum Type {Prince, Princess, King, Queen, NumTypes};
enum Country {England, Belgium, Netherlands, NumCountries};

class Factory {
    static const std::array<std::map<Type, int>, NumCountries> probabilities;
    static std::array<std::map<Type, int>, NumCountries> initializeProbabilities() {
        std::array<std::map<Type, int>, NumCountries> p;
        p[England] =     { {Prince, 29}, {Princess, 60}, {King, 80}, {Queen, 100} };
        p[Belgium] =     { {Prince, 31}, {Princess, 66}, {King, 81}, {Queen, 100} };
        p[Netherlands] = { {Prince, 25}, {Princess, 45}, {King, 90}, {Queen, 100} };
        return p;   
    }
};
const std::array<std::map<Type, int>, NumCountries> Factory::probabilities = initializeProbabilities();

也許他是指地圖的地圖。