Java 爪哇。矩阵中的每个符号出现多少次？

有一个二维数组10x10，填充随机英文字母（大写和小写）如何计数，数组中每个符号出现多少次？

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请检查此解决方案。它将帮助您计算频率

HashMap<Integer,Integer> hm  = new HashMap<>();
    for(int i =0;i<10;i++){
        for(int j=0;j<10;j++){
            if(hm.containsKey(arr[i][j])){
                int freq = hm.get(arr[i][j]);
                hm.put(arr[i][j],++freq);
            } else {
                hm.put(arr[i][j],1);
            }
        }
    }

HashMap hm=newhashmap（）；
对于（int i=0；i使用Java 8流：

import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class CountCharacter {
    public static void main(String[] args) throws Exception {

        Character[][] array = new Character[][] {
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','J'},
            {'A','B','C','D','E','F','G','H','I','a'},
        };



        Map<Character, Long> data =Stream.of(array)
        .flatMap(Stream::of)
        .collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));
        System.out.println(data);
    }

}

您可以将HashMap的使用映射到samePlease、share以及您迄今为止所做的事情。基本思想是，不管数组有多少个维度，您只需要迭代每个项目并计数it@Tatjana我提到了同样的答案。请让我知道，如果你需要帮助了解这一点
    HashMap<Character,Integer> hashMap =new HashMap<>();
    for (Character[] oneD: array) {
        for (Character elem: oneD) {
            hashMap.put(elem, hashMap.getOrDefault(elem, 0)+1);
        }
    }
    System.out.println(hashMap);