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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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88
dynamic_programming/max_sub_array.py
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@ -5,37 +5,41 @@ from typing import List
import time
import matplotlib.pyplot as plt
from random import randint
def find_max_sub_array(A,low,high):
if low==high:
return low,high,A[low]
else :
mid=(low+high)//2
left_low,left_high,left_sum=find_max_sub_array(A,low,mid)
right_low,right_high,right_sum=find_max_sub_array(A,mid+1,high)
cross_left,cross_right,cross_sum=find_max_cross_sum(A,low,mid,high)
if left_sum>=right_sum and left_sum>=cross_sum:
return left_low,left_high,left_sum
elif right_sum>=left_sum and right_sum>=cross_sum :
return right_low,right_high,right_sum
else:
return cross_left,cross_right,cross_sum
def find_max_cross_sum(A,low,mid,high):
left_sum,max_left=-999999999,-1
right_sum,max_right=-999999999,-1
summ=0
for i in range(mid,low-1,-1):
summ+=A[i]
def find_max_sub_array(A, low, high):
if low == high:
return low, high, A[low]
else:
mid = (low + high) // 2
left_low, left_high, left_sum = find_max_sub_array(A, low, mid)
right_low, right_high, right_sum = find_max_sub_array(A, mid + 1, high)
cross_left, cross_right, cross_sum = find_max_cross_sum(A, low, mid, high)
if left_sum >= right_sum and left_sum >= cross_sum:
return left_low, left_high, left_sum
elif right_sum >= left_sum and right_sum >= cross_sum:
return right_low, right_high, right_sum
else:
return cross_left, cross_right, cross_sum
def find_max_cross_sum(A, low, mid, high):
left_sum, max_left = -999999999, -1
right_sum, max_right = -999999999, -1
summ = 0
for i in range(mid, low - 1, -1):
summ += A[i]
if summ > left_sum:
left_sum=summ
max_left=i
summ=0
for i in range(mid+1,high+1):
summ+=A[i]
left_sum = summ
max_left = i
summ = 0
for i in range(mid + 1, high + 1):
summ += A[i]
if summ > right_sum:
right_sum=summ
max_right=i
return max_left,max_right,(left_sum+right_sum)
right_sum = summ
max_right = i
return max_left, max_right, (left_sum + right_sum)
def max_sub_array(nums: List[int]) -> int:
"""
@ -58,22 +62,20 @@ def max_sub_array(nums: List[int]) -> int:
best = max(best, current)
return best
if __name__=='__main__':
inputs=[10,100,1000,10000,50000,100000,200000,300000,400000,500000]
tim=[]
if __name__ == "__main__":
inputs = [10, 100, 1000, 10000, 50000, 100000, 200000, 300000, 400000, 500000]
tim = []
for i in inputs:
li=[randint(1,i) for j in range(i)]
strt=time.time()
(find_max_sub_array(li,0,len(li)-1))
end=time.time()
tim.append(end-strt)
li = [randint(1, i) for j in range(i)]
strt = time.time()
(find_max_sub_array(li, 0, len(li) - 1))
end = time.time()
tim.append(end - strt)
print("No of Inputs Time Taken")
for i in range(len(inputs)):
print(inputs[i],'\t\t',tim[i])
plt.plot(inputs,tim)
plt.xlabel("Number of Inputs");plt.ylabel("Time taken in seconds ")
print(inputs[i], "\t\t", tim[i])
plt.plot(inputs, tim)
plt.xlabel("Number of Inputs")
plt.ylabel("Time taken in seconds ")
plt.show()