使用重复值展平字典数组Swift 3.0

let students = [
    ["name": "Alice", "hobbies": ["reading", "swimming"]],
    ["name": "Bob", "hobbies": ["drawing"]],
    ["name": "Charlie", "hobbies": ["swimming", "dancing"]]
]

// 定义一个空字典，用于存储展平后的结果
var flattenedDictionary: [String: [String]] = [:]

// 定义一个递归函数，用于展平字典数组
func flattenDictionaryArray(_ dictionaryArray: [[String: Any]], currentName: String) {
    for item in dictionaryArray {
        // 获取学生的名字
        guard let name = item["name"] as? String else {
            continue
        }
        
        // 获取学生的爱好
        guard let hobbies = item["hobbies"] as? [String] else {
            continue
        }
        
        // 将每个爱好与对应的学生名字配对
        for hobby in hobbies {
            if let existingHobbies = flattenedDictionary[hobby] {
                // 如果该爱好已经存在于字典中，则将学生名字添加到对应的数组中
                flattenedDictionary[hobby] = existingHobbies + [name]
            } else {
                // 如果该爱好不存在于字典中，则创建一个新的数组
                flattenedDictionary[hobby] = [name]
            }
        }
    }
}

// 调用递归函数，开始展平字典数组
flattenDictionaryArray(students, currentName: "")

// 打印展平后的结果
for (hobby, names) in flattenedDictionary {
    print("\(hobby): \(names)")
}