Python 3: How to compare two big files fastest?
looking up an item in a list takes O(n) time. If you use a dict or a set you can improve it to O(1).
shortest modification you can do is :
linesB = []for line in open('E:/Small_file.txt'): line = json.loads(line) linesB.append(hash(line['uid']))linesB = set(linesB)or to do it right
linesB = set()for line in open('E:/Small_file.txt'): line = json.loads(line) linesB.add(hash(line['uid']))