Faster Ways to Handle Input

In competitive programming or algorithm challenges, using the standard input() can sometimes lead to a TLE (Time Limit Exceeded). Here is how to read data more efficiently using sys.stdin.readline.

Reading Strings

Reading a Single Line

import sys
s = sys.stdin.readline().rstrip()

• Note
  • sys.stdin.readline() includes a newline character (\n) at the end of the string.
  • Therefore, using .rstrip() or .strip() is essential. Since .rstrip() only removes the trailing newline on the right, it is generally slightly faster than .strip().

Reading into a List

1. Creating a list of characters

import sys
char_list = list(sys.stdin.readline().rstrip())

• This approach stores each individual character of the input into a list.

2. Creating a list of words

import sys
word_list = sys.stdin.readline().rstrip().split()

• Assuming the input is space-separated, this stores each word as an element in the list.

Reading Numbers

Multiple Integers in One Line

import sys
a, b = map(int, sys.stdin.readline().split())

• Good to Know
  • The split() function divides a string based on a delimiter.
  • If you leave the arguments empty, it automatically splits the string based on whitespace (spaces, tabs, newlines).