计算Map<String，Map<String，Int>>中元素的数量？通过它的键

import java.util.Map;

public class Main {
    public static void main(String[] args) {
        Map<String, Map<String, Integer>> map = /* 初始化你的Map<String, Map<String, Integer>>对象 */;
        
        int count = 0;
        for (String key : map.keySet()) {
            Map<String, Integer> innerMap = map.get(key);
            count += innerMap.keySet().size();
        }
        
        System.out.println("元素的数量为：" + count);
    }
}