python - 在 Python 中有效地比较两个文件中的行

Question

我正在尝试比较两条线并捕获彼此匹配的线。例如，
file1.txt 包含

my
sure

file2.txt 包含

my : 2
mine : 5
sure : 1

我正在尝试输出

my : 2
sure : 1

到目前为止，我有以下代码

inFile = "file1.txt"
dicts = "file2.txt"


with open(inFile) as f:
    content = f.readlines()

content = [x.strip() for x in content]

with open(dicts) as fd:
    inDict = fd.readlines()

inDict = [x.strip() for x in inDict]

ordered_dict = {}

for line in inDict:
    key = line.split(":")[0].strip()
    value = int(line.split(":")[1].strip())
    ordered_dict[key] = value

for (key, val) in ordered_dict.items():
    for entry in content:
        if entry == content:
            print(key, val)
        else:
            continue

然而，这是非常低效的，因为它循环了两次并且迭代了很多次。因此，这对于大文件来说并不理想。我怎样才能使它适用于大文件？

Answer 1

您不需要嵌套循环。一个循环读取 file2 并转换为 dict，另一个循环读取 file1 并查找结果。

inFile = "file1.txt"
dicts = "file2.txt"

ordered_dict = {}
with open(dicts) as fd:
    for line in fd:
        a,b = line.split(' : ')
        ordered_dict[a] = b

with open(inFile) as f:
    for line in f:
        line = line.strip()
        if line in ordered_dict:
            print( line, ":", ordered_dict[line] )

第一个循环可以作为列表理解来完成。

with open(dicts) as fd:
    ordered_dict = dict( line.strip().split(' : ') for line in fd )