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psf/black code formatting (#1277)

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This commit is contained in:
William Zhang
2019-10-05 01:14:13 -04:00
committed by Christian Clauss
parent 07f04a2e55
commit 9eac17a408
291 changed files with 6014 additions and 4571 deletions
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81
dynamic_programming/edit_distance.py
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@ -19,37 +19,41 @@ class EditDistance:
def __init__(self):
self.__prepare__()
def __prepare__(self, N = 0, M = 0):
self.dp = [[-1 for y in range(0,M)] for x in range(0,N)]
def __prepare__(self, N=0, M=0):
self.dp = [[-1 for y in range(0, M)] for x in range(0, N)]
def __solveDP(self, x, y):
if (x==-1):
return y+1
elif (y==-1):
return x+1
elif (self.dp[x][y]>-1):
if x == -1:
return y + 1
elif y == -1:
return x + 1
elif self.dp[x][y] > -1:
return self.dp[x][y]
else:
if (self.A[x]==self.B[y]):
self.dp[x][y] = self.__solveDP(x-1,y-1)
if self.A[x] == self.B[y]:
self.dp[x][y] = self.__solveDP(x - 1, y - 1)
else:
self.dp[x][y] = 1+min(self.__solveDP(x,y-1), self.__solveDP(x-1,y), self.__solveDP(x-1,y-1))
self.dp[x][y] = 1 + min(
self.__solveDP(x, y - 1),
self.__solveDP(x - 1, y),
self.__solveDP(x - 1, y - 1),
)
return self.dp[x][y]
def solve(self, A, B):
if isinstance(A,bytes):
A = A.decode('ascii')
if isinstance(A, bytes):
A = A.decode("ascii")
if isinstance(B,bytes):
B = B.decode('ascii')
if isinstance(B, bytes):
B = B.decode("ascii")
self.A = str(A)
self.B = str(B)
self.__prepare__(len(A), len(B))
return self.__solveDP(len(A)-1, len(B)-1)
return self.__solveDP(len(A) - 1, len(B) - 1)
def min_distance_bottom_up(word1: str, word2: str) -> int:
@ -63,38 +67,37 @@ def min_distance_bottom_up(word1: str, word2: str) -> int:
"""
m = len(word1)
n = len(word2)
dp = [[0 for _ in range(n+1) ] for _ in range(m+1)]
for i in range(m+1):
for j in range(n+1):
dp = [[0 for _ in range(n + 1)] for _ in range(m + 1)]
for i in range(m + 1):
for j in range(n + 1):
if i == 0: #first string is empty
if i == 0: # first string is empty
dp[i][j] = j
elif j == 0: #second string is empty
elif j == 0: # second string is empty
dp[i][j] = i
elif word1[i-1] == word2[j-1]: #last character of both substing is equal
dp[i][j] = dp[i-1][j-1]
elif (
word1[i - 1] == word2[j - 1]
): # last character of both substing is equal
dp[i][j] = dp[i - 1][j - 1]
else:
insert = dp[i][j-1]
delete = dp[i-1][j]
replace = dp[i-1][j-1]
insert = dp[i][j - 1]
delete = dp[i - 1][j]
replace = dp[i - 1][j - 1]
dp[i][j] = 1 + min(insert, delete, replace)
return dp[m][n]
if __name__ == '__main__':
solver = EditDistance()
print("****************** Testing Edit Distance DP Algorithm ******************")
print()
S1 = input("Enter the first string: ").strip()
S2 = input("Enter the second string: ").strip()
print()
print("The minimum Edit Distance is: %d" % (solver.solve(S1, S2)))
print("The minimum Edit Distance is: %d" % (min_distance_bottom_up(S1, S2)))
print()
print("*************** End of Testing Edit Distance DP Algorithm ***************")
if __name__ == "__main__":
solver = EditDistance()
print("****************** Testing Edit Distance DP Algorithm ******************")
print()
S1 = input("Enter the first string: ").strip()
S2 = input("Enter the second string: ").strip()
print()
print("The minimum Edit Distance is: %d" % (solver.solve(S1, S2)))
print("The minimum Edit Distance is: %d" % (min_distance_bottom_up(S1, S2)))
print()
print("*************** End of Testing Edit Distance DP Algorithm ***************")