python中不相交集的初始化

Question

我有一些关于不相交集的代码。

import set
import copy
"""
Importing set.py should provide the following functions:

set.Initialize(Values)       -- return a new set system with one element
                                per set.

                                Values is a list of values for the
                                sets

set.Find(set, value)         -- Return the name of the set in which value lives.
                                Do path compression.

                                Exactly what you return isn't
                                important, as long as Find(set,
                                val1) and Find(set, val2) are
                                equal if and only if val1 and val2
                                are in the same set.

set.Merge(set, value1, value2)  -- Merge operation.  Make sure you parent
                                   the smaller set to the larger.

"""

import random
import time


random.seed(time.time())
A = []                                  
passed=True
# First make a list of stuff for the set system
for i in range(1000):
    val = random.randrange(-1000,1000)
    if(val not in A):
        A.append(val)
MyA = copy.deepcopy(A)

my_set = set.Initialize(A)

# Now randomly do finds and unions until everything is in the same set.
print "Doing lots of finds and unions..."
while(MyA.count(MyA[0]) != len(A)):
    # raw_input("Press any key...")
    length = len(A)
    index_1 = random.randrange(0, length)
    val_1 = A[index_1]
    index_2 = random.randrange(0, length)
    val_2 = A[index_2]
    if(random.randrange(1,6) < 3):

    # With probability 2/5, do a find
    set_says = (set.Find(my_set, val_1) == set.Find(my_set, val_2))
    A_says = (MyA[index_1] == MyA[index_2])
    # print "Find ",val_1,"=",set.Find(my_set, val_1)
    # print "Find ",val_2,"=",set.Find(my_set, val_2)
    if(set_says != A_says):
        passed=False
        print "Oops: I said Find(", val_1, ") == Find(", val_2, ") and got ", set_says
    else:
        # Otherwise (with probability 3/5), do a union
        set1=MyA[index_1]
        set2=MyA[index_2]
        for i in range(len(MyA)):
            if(MyA[i] == set1):
                MyA[i] = set2
        set.Merge(my_set, val_1, val_2)
        # print "Merging ",val_1, "and", val_2
# print A
# print MyA
# Now verify that everything is in the same set.  Start with set.py.
print "Checking that everything is in one set now..."
val = set.Find(my_set, A[0])
for i in range(len(A)):
val2 = set.Find(my_set, A[i])
if(val != val2):
  passed=False
  print "Oops, ", val, " and ", val2, " should be in the same set, but aren't."

print "Verifying the test harness..."
val = MyA[0]
for i in range(len(MyA)):
    if(MyA[i] != val):
        print "Uh, oh, it looks like the test harness itself has a bug."
if passed:
    print "All tests passed!"

我想添加查找，合并和初始化功能。在代码的顶部，它告诉每个函数必须做什么。我已经找到并合并，我希望他们是对的。但是我无法获得初始化功能。我不知道如何让它返回一个新的集合系统，每组一个元素。你能帮帮我吗？

以下是我的查找和合并功能：

def Find(set,x):
    if set[x] == set[x].parent:
        return set[x]
    set[x].parent = Find(set,set[x].parent)
    return set[x].parent

def Merge(set, labelA, labelB):
    pa = Find(set, labelA)
    pb = Find(set, labelB)
    if pa == pb: 
        return #They are already joined
    parent = pa
    child = pb
    if pa.rank < pb.rank:
        parent = pb
        child = pa
    child.parent = parent
    parent.rank = max(parent.rank, child.rank+1)