最近看了《演算法**》，覺得很棒，做一些總結記錄。
# -*- coding: utf-8 -*-
import random
__author__ = "chenk"
class algorithme:
""""""
def __init__(self):
self.low = 0
self.high = 10000
def get_random_num(self):
"""return a random num. the num is between 0 and 10000."""
return random.randint(self.low, self.high)
def get_list(self, num):
"""returns an array of the number of executions."""
num_list = list()
while num:
num -= 1
return num_list
def dichotomy(self):
"""二分法猜數字： a給出乙個整數num(0num:
high = mid
elif mid < num:
low = mid
else:
print("you got it. it takes %d times." % count)
break
mid = (low + high) // 2
def get_max_num(self, array):
"""from the array get the max num."""
max_num = 0
for num in array:
if num > max_num:
max_num = num
return max_num
def selection_sort(self):
"""選擇排序(從大到小)：每次從陣列中取最大的值，迴圈 n/2 次。
num_list = self.get_list(20)
sorted_list = list()
print("選擇排序目標陣列:\n", num_list)
for i in range(len(num_list)):
max_num = self.get_max_num(num_list)
num_list.remove(max_num)
return sorted_list
def quicksort(self, array):
"""快速排序(從大到小).
if len(array) < 2:
return array
else:
pivot = array[0]
left = [i for i in array[1:] if i >= pivot]
right = [i for i in array[1:] if i < pivot]
return self.quicksort(left) + [pivot] + self.quicksort(right)
if __name__ == "__main__":
algorithme = algorithme()
for i in range(10):
algorithme.dichotomy()
sorted_list = algorithme.selection_sort()
print("排序後的值:\n", sorted_list)
quicksort_list = algorithme.get_list(10)
print("快速排序目標陣列：\n", quicksort_list)
quicksort = algorithme.quicksort(quicksort_list)
print("排序後的值:\n", quicksort)
the random num is 3432.
you got it. it takes 11 times.
the random num is 9185.
you got it. it takes 12 times.
the random num is 8764.
you got it. it takes 11 times.
the random num is 6344.
you got it. it takes 12 times.
the random num is 667.
you got it. it takes 13 times.
the random num is 5982.
you got it. it takes 12 times.
the random num is 7408.
you got it. it takes 12 times.
the random num is 450.
you got it. it takes 12 times.
the random num is 2013.
you got it. it takes 12 times.
the random num is 5428.
you got it. it takes 14 times.
選擇排序目標陣列:
[42, 607, 2544, 3854, 4845, 9129, 1208, 1286, 7588, 9414, 6669, 3927, 8941, 6775, 9866, 2526, 9410, 9463, 1048, 2010]
排序後的值:
[9866, 9463, 9414, 9410, 9129, 8941, 7588, 6775, 6669, 4845, 3927, 3854, 2544, 2526, 2010, 1286, 1208, 1048, 607, 42]
快速排序目標陣列：
[4563, 6788, 628, 4224, 4286, 4563, 4503, 9094, 5353, 8843]
排序後的值:
[9094, 8843, 6788, 5353, 4563, 4563, 4503, 4286, 4224, 628]
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