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psf/black code formatting (#1277)

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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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64
dynamic_programming/matrix_chain_order.py
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@ -1,44 +1,54 @@
import sys
'''
"""
Dynamic Programming
Implementation of Matrix Chain Multiplication
Time Complexity: O(n^3)
Space Complexity: O(n^2)
'''
def MatrixChainOrder(array):
N=len(array)
Matrix=[[0 for x in range(N)] for x in range(N)]
Sol=[[0 for x in range(N)] for x in range(N)]
"""
for ChainLength in range(2,N):
for a in range(1,N-ChainLength+1):
b = a+ChainLength-1
def MatrixChainOrder(array):
N = len(array)
Matrix = [[0 for x in range(N)] for x in range(N)]
Sol = [[0 for x in range(N)] for x in range(N)]
for ChainLength in range(2, N):
for a in range(1, N - ChainLength + 1):
b = a + ChainLength - 1
Matrix[a][b] = sys.maxsize
for c in range(a , b):
cost = Matrix[a][c] + Matrix[c+1][b] + array[a-1]*array[c]*array[b]
for c in range(a, b):
cost = (
Matrix[a][c] + Matrix[c + 1][b] + array[a - 1] * array[c] * array[b]
)
if cost < Matrix[a][b]:
Matrix[a][b] = cost
Sol[a][b] = c
return Matrix , Sol
#Print order of matrix with Ai as Matrix
def PrintOptimalSolution(OptimalSolution,i,j):
if i==j:
print("A" + str(i),end = " ")
return Matrix, Sol
# Print order of matrix with Ai as Matrix
def PrintOptimalSolution(OptimalSolution, i, j):
if i == j:
print("A" + str(i), end=" ")
else:
print("(",end = " ")
PrintOptimalSolution(OptimalSolution,i,OptimalSolution[i][j])
PrintOptimalSolution(OptimalSolution,OptimalSolution[i][j]+1,j)
print(")",end = " ")
print("(", end=" ")
PrintOptimalSolution(OptimalSolution, i, OptimalSolution[i][j])
PrintOptimalSolution(OptimalSolution, OptimalSolution[i][j] + 1, j)
print(")", end=" ")
def main():
array=[30,35,15,5,10,20,25]
n=len(array)
#Size of matrix created from above array will be
array = [30, 35, 15, 5, 10, 20, 25]
n = len(array)
# Size of matrix created from above array will be
# 30*35 35*15 15*5 5*10 10*20 20*25
Matrix , OptimalSolution = MatrixChainOrder(array)
Matrix, OptimalSolution = MatrixChainOrder(array)
print("No. of Operation required: "+str((Matrix[1][n-1])))
PrintOptimalSolution(OptimalSolution,1,n-1)
if __name__ == '__main__':
print("No. of Operation required: " + str((Matrix[1][n - 1])))
PrintOptimalSolution(OptimalSolution, 1, n - 1)
if __name__ == "__main__":
main()