The number of tasks included in the service portfolio is 4; Each task corresponds to 1000 cloud services with the same functional attributes and different non-functional attributes; By default, the output of the first task is the input of the second task, the output of the second task is the input of the third task, and so on; The non-functional properties of each service consist of five: execution price (The range is: [0,100] RMB), execution time (The range is: [20,200] ms), probability of success (The range is: [0,1]), availability (The range is: [0,1]), reputation(The range is: [0,10])； Each dimension attribute of cloud service needs to be normalized; Calculation formula for quality of service: execution price ∑ execution time ∑ probability of success ∏ availability ∏ reputation Average The input is a quadruple (i, j, k, c), and the output is the QoS value of the combined service, That is, four cloud services are composited: the i-th service in the first service library, the j-th service in the second service library, the k-th service in the third service library, and the c-th service in the fourth service library.

这是一个关于云服务组合的问题，根据提供的信息，可以计算出组合服务的质量。输入是一个四元组(i, j, k, c)，输出是组合服务的QoS值。每个任务包含100个云服务，每个服务有不同的非功能属性，需要进行归一化处理。计算QoS值的公式包括执行价格、执行时间、成功概率、可用性和声誉等五个维度。