import timeit
import matplotlib.pyplot as plt
# 第一種演算法時間複雜度達到o(n^2)
def anagramsolution1(s1, s2):
'''查詢兩個字串是否是相互亂序, 也就是兩個字串的字元排序不一樣
'''alist = list(s2)
pos1 = 0
stillok = true
while pos1 < len(s1) and stillok:
pos2 = 0
found = false
# 從乙個字元當中每次取乙個字元依次在另乙個字串中查詢
while pos2 < len(s2) and not found:
if s1[pos1] == alist[pos2]:
found = true
else:
pos2 = pos2 + 1
# 如果查詢到該字元在另乙個字串中存在，就將該位置 的字元值為零，
# 以免出現例如"accc" 和 "aacc"相匹配的情況
if found:
alist[pos2] = none
else:
stillok = false
pos1 = pos1 + 1
return stillok
# 第二種演算法是先把所有的需要匹配的字元創排好序， 那麼對應排好序的字串應該都是一模一樣的
# 演算法時間也達到幾乎o(n^2),乙個來自於排序演算法，乙個來自於比較演算法
def anagramsolution2(s1, s2):
alist1 = list(s1)
alist2 = list(s2)
alist1.sort()
alist2.sort()
pos = 0
flag = true
while pos < len(s1) and flag:
if alist1[pos] == alist2[pos]:
pos += 1
else:
flag = false
return flag
# 第三種演算法是假設所有的字串都是包含小寫的字元，那麼就對每乙個字元出現的次數計數
# 然後對應的字元計數相比較，演算法時間複雜度o(n)
def anagramsolution3(s1, s2):
c1 = [0]*26
c2 = [0]*26
for i in range(len(s1)):
# 取得asci瑪的數值
pos = ord(s1[i]) - ord('a')
c1[pos] = c1[pos] + 1
for i in range(len(s2)):
# 取得asci瑪的數值
pos = ord(s2[i]) - ord('a')
c2[pos] = c2[pos] + 1
j, flag = 0, true
while j < 26 and flag:
if c1[j] == c2[j]:
j += 1
else:
flag = false
return flag
def test1():
l =
for i in range(1000):
l = l + [i]
def test2():
l =
for i in range(1000):
def test3():
l = [i for i in range(1000)]
def test4():
l = list(range(1000))
if __name__ == '__main__':
print(anagramsolution1('abcd', 'dcba'))
print(anagramsolution2('abcd', 'dcba'))
print(anagramsolution3('abcd', 'dcba'))
print("-----------------------------")
t1 = timeit.timer("test1()", "from __main__ import test1")
t2 = timeit.timer("test2()", "from __main__ import test2")
t3 = timeit.timer("test3()", "from __main__ import test3")
t4 = timeit.timer("test4()", "from __main__ import test4")
print("concat ", t1.timeit(number=1000), "millseconds")
print("comprehension ", t3.timeit(number=1000), "millseconds")
print("list range ", t4.timeit(number=1000), "millseconds")
print('-------------------------------')
popzero = timeit.timer('x.pop(0) ', 'from __main__ import x')
popend = timeit.timer('x.pop() ', 'from __main__ import x')
'''x = list(range(90000000))
print('pop zero ', popzero.timeit(number=1000), 'millseconds')
x = list(range(90000000))
print('pop end ', popend.timeit(number=1000), 'millseconds')
'''for i in range(100000, 100000001, 100000):
x = list(range(i))
pt = popend.timeit(number=1000)
x = list(range(i))
pz = popzero.timeit(number=1000)
i = len(x)
plt.scatter(i, int(pt), 'o', title='pop end')
plt.scatter(i, int(pz), '-', title='pop zero')
plt.grid(true)
plt.legend(loc='upper left')
plt.show()
print('pt = ', pt)
print('pz = ', pz)
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