Dynamic programming--task schedule

a=[2,4,3,6,1]
b=[5,2,3,1,7]

tasks = zip(a,b)
tasks_no= zip(tasks, range(1,6))
_list1 = sorted(filter(lambda item:item[0][0] < item[0][1], tasks_no))
_list2 = sorted(filter(lambda item:item[0][0] >=item[0][1], tasks_no),
             key = lambda item:item[0][1], reverse=True)
_list = _list1 + _list2

_res =  zip(*_list)[1]
_seq = zip(*_list)[0]
print _seq
_seq2= zip(*_seq)

part1 = _list[0][0][0]
part2 = part1 + _list[0][0][1]

 

for i in  range(1,5):
 part1 = part1 + _list[i][0][0]
 part2 = part1 + _list[i][0][1] if part1>part2 else part2+_list[i][0][1]

print part2