#P9834. PSO
PSO
PSO
Problem Description
Particle swarm optimization ( PSO ) is a population-based stochastic optimization algorithm. In addition to the basic structure of PSO, there is also a variant called star-topology PSO, which introduces a star-shaped communication structure among particles. In this structure, there is a central particle called the leader, which is responsible for gathering and disseminating information to the rest of the particles in the swarm. Now there are particles on the star-topology. Among the particles, there is one particle as the leader, and there is an edge between the other particles and the leader. For a piece of information, it can be propagated along an edge on the topology. To examine the benefits of this topology, we need to calculate the following data: We define that is number of edges required for them to exchange information for two different particles. Please calculate the expected value and maximum value of .
Input
The first line of input is a positive integer representing the number of test cases. For each line,input a number .
Output
For each case, output two floating-point numbers representing the he expected value rounde off and maximum value of . (keep decimal places)
Sample Input
2
4
7
Sample Output
1.500000000 2.000000000
1.714285714 2.000000000
Source
2023“钉耙编程”中国大学生算法设计超级联赛(4)