如何爲地圖創建自己的比較器？ - How can I create my own comparator for a map?

問題：

typedef map<string, string> myMap;

When inserting a new pair to myMap , it will use the key string to compare by its own string comparator.向myMap插入新對時，它將使用鍵string通過其自己的字符串比較器進行比較。 Is it possible to override that comparator?是否可以覆蓋該比較器？ For example, I'd like to compare the key string by its length, not by the alphabet.例如，我想通過長度而不是字母來比較鍵string 。 Or is there any other way to sort the map?或者有沒有其他方法可以對地圖進行排序？

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解決方案：

參考： https://stackoom.com/en/question/O3Tq