Input and Output

Taking input and showing output in the required way plays an important role in interactive coding. So let's focus on input and output of various data types.

input()

Use input() to read a line of text from stdin. It always returns a string, so convert it to the data type you need with int(), float(), or str().

# Prints out the input received from stdin
astring = input()          # give hello as input
print(astring)

After taking the input we can convert it to our required data type using functions like int(), float(), str():

num = int(input())
print(num)

decimalnum = float(input())
print(decimalnum)

How to take two or more data types as input from a single line separated by spaces?

Here we make use of split() and map() functions:

# give two integers in the first line, and more than two integers in the third line
a, b = map(int, input().split())
array = input().split()
total = 0
for each in array:
    total = total + int(each)
print(a, b, total)  # prints the first two integers from the first line and the sum of the integers of the second line

Output formatting

You might have already noticed that the print statement automatically inserts a new line. The use of a comma like in the above code prints the values on a single line separated by a space. The sys module provides various functions for output formatting, but here we learn how to use basic knowledge of formatting to output in our required way. Let's see a few examples to learn output formatting:

a = 5
b = 0.63
c = "hello"
print("a is : %d, b is %0.4f, c is %s" % (a, b, c))

The output must be self explanatory.

Exercise

Complete the code below so that it reads three integers from a single line, converts each to an int, and prints their sum.

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