def select_sort(tList):
if not tList:
return
for i in range(1, len(tList)):
min = i-1
for j in range(i, len(tList)):
if tList[j] < tList[min]:
min = j
swap(tList, i-1, min)
def extract_max(self):
""" return and remove the top element """
if self.size == 0:
return None
max = self._list[0]
swap(self._list, 0, self.size-1)
self.size = self.size-1
if self.size > 1:
self._down_heapify(0)
return max
def _down_heapify(self, index):
left = index*2+1
right = left+1
max = index
if left<self.size and self._is_bigger(left, max):
max = left
if right<self.size and self._is_bigger(right, max):
max = right
if max != index:
swap(self._list, max, index)
self._down_heapify(max)
def bubble_sort(tList):
if not tList:
return
for i in range(len(tList)-1, 0, -1):
exchange = False
for j in range(1, i+1):
if tList[j] < tList[j-1]:
swap(tList, j, j-1)
exchange = True
if not exchange:
break
def perm(tList, cbk, start=None, end=None):
"""
generate the permutation of tList, for each list in the permutation result,
call cbk(list)
start is the first index, None means 0
end is the last index, None means len(tList)-1
"""
if start is None:
start = 0
if end is None:
end = len(tList)-1
if start>=end:
cbk(tList)
return
for i in range(start, end+1):
swap(tList, start, i)
perm(tList, cbk, start+1, end)
swap(tList, start, i)
def partition(tList, start, end):
p = random.randint(start, end)
mValue = tList[p]
swap(tList, start, p)
i,j = start+1,end
while i<=j:
while i<=j and tList[i]<=mValue:
i = i+1
while i<=j and tList[j]>=mValue:
j = j-1
if i<j:
swap(tList, i, j)
i = i+1
j = j-1
p = i-1
swap(tList, start, p)
return p
def exchange(i, j):
swap(tList, i, j)
swap(flags, i, j)
def sort(tList):
for j in range(len(tList)-1, 0, -1):
for i in range(1, j+1):
if tList[i] < tList[i-1]:
swap(tList, i, i-1)
def _top_heapify(self, index):
parent = (index-1)/2
if parent>=0 and self._is_bigger(index, parent):
swap(self._list, index, parent)
self._top_heapify(parent)