Using Sys.stdin.readline() To Read Multiple Lines From Cmd In Python

I'd like to type in my input from command lines after running if __name__ == '__main__': data = list(map(int, sys.stdin.readline().split())) print(data) n, capacity = d

Solution 1:

The solution to this problem depends on the OS you're using. Basically, if you want multiline input, you'll have to use sys.stdin.read() instead of sys.stdin.readline(). Since sys.stdin is a file-like object in Python, the read() method will read until it reaches the end of a file. It is marked by a special character EOF (end-of-file). On different OS'es there is a different way of sending it.

On Windows: Press Ctrl+Z after your input and then press Enter:

2 10
20 2
30 3
^Z

On a Unix-based OS: Press Ctrl+D after your input. No Enter is required (I believe)

If you want to get a list [2, 10, 20, 2, 30, 3] from your input, you're fine. The split() method splits by whitespace (spaces, newlines, etc.).

Solution 2:

I agree with everything @Leva7 has said. Nonetheless, I'd suggest another solution, which is to use raw_input for Python 2 or input for Python 3 like so:

args = []
s = raw_input()                # input() for Python 3while s != '':
    args.extend([int(arg) forargin s.strip().split()])
    s = raw_input()

Of course, that's not a one-liner in any way, but it does the job and it's easy to see how it's done. Plus, no special characters are required at the end of the input.

Solution 3:

If you are on Windows make sure you finish your input with newline, otherwise ^Z (from pressing Ctrl-Z) will be included in your input. Also make sure you use English language layout - https://stackoverflow.com/a/17924627/9205085