In competitive programming, it is often necessary to parse input data in order to solve the problem at hand. Python provides multiple ways to read input from the user.
One way to read input from the user is through the use of the input() function. This function takes a single argument, which is a string that will be displayed to the user before reading the input. The input() function returns a string containing the text that was typed by the user.
Another way to read input from the user is through the use of the raw_input() function. This function takes a single argument, which is a string that will be displayed to the user before reading the input. The raw_input() function returns a string containing the text that was typed by the user, including any trailing newline characters.
A third way to read input from the user is through the use of the get_input() function. This function takes two arguments: the first is a string that will be displayed to the user before reading the input, and the second is a boolean value that indicates whether or not leading and trailing whitespace should be stripped from the input string. The get_input() function returns a string containing the text that was typed by the user, with any leading and trailing whitespace characters removed.
Finally, it is also possible to read a single character of input from the user by using the fetch() function. This function takes no arguments and simply returns a string containing the next character of input from the user. Note that this function will not work on all systems - in particular, it will not work on Windows systems.
There are many ways to take input in Python. But, some methods are more suitable for competitive programming than others. In this article, we will discuss the different input methods and how to use them for competitive programming.
1) Input via the command line:
The easiest way to take input is via the command line. You can simply type the input values after the program name while running it.
python program.py 1 2
This would store the value 1 in the first variable and 2 in the second variable. However, this method is not very efficient, especially if you have a lot of input values.
2) Input via the ‘input()’ function:
A more efficient way to take input is via the ‘input()’ function. This function takes a single argument, which is the prompt message. It then prints the message and waits for the user to enter a value. For example, if we want to take two inputs, 1 and 2, we would write:
a = input("Enter first value: ") b = input("Enter second value: ")
This would print “Enter first value: ” and wait for the user to enter a value. After the user enters a value (say 1), it would store it in the ‘a’ variable. Then, it would print “Enter second value: ” and wait for the user to enter a value (say 2). Finally, it would store the value 2 in the ‘b’ variable.
3) Input via the ‘sys. stdin’ module:
Another way to take input is via the ‘sys. stdin’ module. This module provides a file-like object called ‘stdin’, which you can use to read input values. For example, if we want to take two inputs, 1 and 2, we would write:
import sys
a = sys.stdin.readline()
b = sys.stdin.readline()
This would store the value 1 in the ‘a’ variable and 2 in the ‘b’ variable.
4) Input via the ‘raw_input()’ function:
The ‘raw_input()’ function is similar to the ‘input()’ function, except that it returns a string instead of a number. For example, if we want to take two inputs, 1 and 2, we would write:
a = raw_input("Enter first value: ")
b = raw_input("Enter second value: ")
This would store the value “1” in the ‘a’ variable and “2” in the ‘b’ variable.
5) Input via the ‘fileinput’ module:
Another way to take input is via the ‘fileinput’ module. This module provides a file-like object called ‘stdin’, which you can use to read input values from a file. For example, if we have an input file named ‘input.txt’ with two lines, 1 and 2, we would write:
import fileinput
for line in fileinput.input():
print int(line)
This would print 1 and 2 on separate lines. These are some of the ways to take input in Python. You can choose any one of these methods depending on your requirements.
