How to read all inputs from STDIN in Hackerrank?-CodePudding

I have learned some basics of Python and wanted to try easy challenges in Hackerrank.

Input format: the first line contains integer, the second line contains the space separated list of integers, and third line contains another integer.

In codding part, it says # Enter your code here. Read input from STDIN. Print output to STDOUT

I am having difficulty of reading and saving from STDIN. I want to save the first line integer as X, second line list as list and third line integer as N.

I don't understand how to do it. I have googled and tried to use some existing codes, but keep getting errors.

CodePudding user response：

You can use input:

# the first line contains integer
integer1 = int(input())

# the second line contains the space separated list of integers
int_lst = list(map(int, input().split()))

# third line contains another integer.
integer2 = int(input())

list of lists for 10 lines:

lst = [list(map(int, input().split())) for _ in range(10)]

CodePudding user response：

We can use the input() to receive the input from STDIN and cast it to int as the input() function returns the STDIN as string.

To receive an integer:

>>> x = int(input().strip())
12
>>> x
12

To convert the list of space separated integers to list:

>>> y = list(map(int,input().strip().split(' ')))
1 2 3 4 556
>>> y
[1, 2, 3, 4, 556]

To create 2D list of integers:

>>> rows = 3
>>> array = []
>>> for i in range(rows):
...     each_line = list(map(int,input().strip().split(' ')))
...     array.append(each_line)
...
1 2 3
4 5 6
7 8 9
>>> array
[[1, 2, 3], [4, 5, 6], [7, 8, 9]]