查找组中出现次数最多的值

def find_most_frequent_value(arr):
    freq_dict = {}
    max_freq = 0
    most_frequent_values = []
    
    # 计算每个元素的出现次数
    for value in arr:
        if value in freq_dict:
            freq_dict[value] += 1
        else:
            freq_dict[value] = 1

        # 更新最大次数
        if freq_dict[value] > max_freq:
            max_freq = freq_dict[value]
    
    # 找到出现次数最多的值
    for key, value in freq_dict.items():
        if value == max_freq:
            most_frequent_values.append(key)
    
    return most_frequent_values

# 示例用法
arr = [1, 2, 3, 2, 1, 2, 3, 3, 4, 5, 4]
result = find_most_frequent_value(arr)
print("出现次数最多的值：", result)