Stock trading

input01.txt

10
9
94 66 53 82 87 89 69 24 56
6
65 80 74 98 1 15
5
3 72 72 95 63
6
7 74 34 81 100 5
7
34 65 16 79 66 16 28
9
41 42 62 31 49 24 68 3 30
9
94 70 86 9 43 87 65 6 80
4
35 84 31 26
5
58 31 84 77 42
10
2 21 93 16 20 20 10 67 32 8

output01.txt

100
89
138
204
134
186
229
49
79
365

stocktrading.py

import sys

def main():
	if type(sys.stdin).__name__!='file':
		sys.exit()
	else:
		data=[]
		for line in sys.stdin:
			data.append(line.strip())
		cases=int(data[0])
		data=data[1:]
		if len(data)%2!=0|len(data)/2!=cases:
			sys.exit()
		else:
			for evenrow in range(0,len(data)-1,2):
				process(data[evenrow],map(int,data[evenrow+1].split(' ')))

def process(days,prices):
	if days<2:
		print 0
	else:
		indices=range(len(prices))
		indices.sort(lambda x,y:prices[y]-prices[x])
		
		total_profit=0
		i=0
		for j in indices:
			if j>i:
				total_profit+=calculate_profit(prices[i:j+1])
			i=max(i,j+1)
			if i==len(prices):
				break
		print total_profit

def calculate_profit(prices):
	revenue=(len(prices)-1)*prices[-1]
	cost=sum(prices[:len(prices)-1])
	return revenue-cost

if __name__=='__main__':
	main()