HackerRank Solution: String Formatting [3 Methods]

Question: Python String Formatting [Strings]

Given an integer, n, print the following values for each integer i from 1 to n:

Decimal
Octal
Hexadecimal (capitalized)
Binary

Function Description

Complete the print_formatted function in the editor below.

print_formatted has the following parameters:

int number: the maximum value to print

Prints

The four values must be printed on a single line in the order specified above for each i from 1 to n. Each value should be space-padded to match the width of the binary value of number and the values should be separated by a single space.

Input Format

A single integer denoting n.

Constraints

1 <= n <= 99

Sample Input

Sample Output:

    1     1     1     1
    2     2     2    10
    3     3     3    11
    4     4     4   100
    5     5     5   101
    6     6     6   110
    7     7     7   111
    8    10     8  1000
    9    11     9  1001
   10    12     A  1010
   11    13     B  1011
   12    14     C  1100
   13    15     D  1101
   14    16     E  1110
   15    17     F  1111
   16    20    10 10000
   17    21    11 10001

Possible Solutions

Now let us go through the possible solutions for the given problem. The following code is already given in the editor of the Hacker Rank.

def print_formatted(number):
    # your code goes here

if __name__ == '__main__':
    n = int(input())
    print_formatted(n)

We have to complete the function.

Solution-1: Using for loop

Let us first solve the problem using for loop and then we will explain the code.

def print_formatted(number):
    pad = number.bit_length()
    for i in range(1,number+1):
        print(str(i).rjust(pad),oct(i).split("o")[1].rjust(pad),hex(i).split("x")[1].upper().rjust(pad),bin(i).split("b")[1].rjust(pad))
if __name__ == '__main__':
    n = int(input())
    print_formatted(n)

This solution defines a function ‘print_formatted’ which takes an integer ‘number’ as input and prints the decimal, octal, hexadecimal, and binary representation of the integers from 1 to ‘number’ in a formatted way, with each representation aligned vertically. The width of the output is determined by the number of bits required to represent the largest number, ‘number’, and all the other representations are padded with spaces to match this width. If this code is run as the main program, it takes an input ‘n’ and calls the ‘print_formatted’ function with ‘n’ as its argument.

Solution-2: Formating the numbers

Let us now use the format method to solve the given problem.

def print_formatted(number):
    nbin = format(number,'b')
    size = len(nbin)
    for i in range(1,n+1):
        octa = format(i,'o')
        hexa = format(i,'X')
        bina = format(i,'b')

        print(str(i).rjust(size),str(octa).rjust(size),str(hexa).rjust(size),str(bina).rjust(size))
if __name__ == '__main__':
    n = int(input())
    print_formatted(n)

This code defines a function ‘print_formatted’ that takes an integer ‘number’ as input and prints the decimal, octal, hexadecimal, and binary representations of the integers from 1 to ‘number’, each representation aligned vertically. The function first calculates the binary representation of ‘number’ and determines the number of bits required to represent it. It then formats each integer from 1 to ‘number’ in octal, hexadecimal, and binary representation using the ‘format’ function, with each representation padded with spaces to match the width determined by the binary representation of ‘number’. The function finally prints the decimal, octal, hexadecimal, and binary representations of each integer from 1 to ‘number’ in a formatted way, with each representation aligned vertically.

Solution-3: Alternative method

In Python, we can use the same code in various ways. Let us solve the given problem using a different method and then will explain the code in detail.

def print_formatted(upto: int):
    w = upto.bit_length()
    for num in range(1, upto + 1):
        print(f"{num:>{w}d} {num:>{w}o} {num:>{w}X} {num:>{w}b}")
if __name__ == '__main__':
    n = int(input())
    print_formatted(n)

similar to other solutions, this code defines a function ‘print_formatted’ that takes an integer ‘upto’ as input and prints the decimal, octal, hexadecimal, and binary representations of the integers from 1 to ‘upto’, each representation aligned vertically. Unlike the previous code, this code uses the format specifier ‘f-string’ to format the output in a more concise way. It first calculates the number of bits required to represent ‘upto’ using the ‘bit_length’ method, and then uses this value to determine the width of each representation. The format specifier ‘:>{w}d’ represents decimal representation, ‘:>{w}o’ represents octal representation, ‘:>{w}X’ represents hexadecimal representation, and ‘:>{w}b’ represents binary representation. This code uses the format specifier in each print statement to format the output and align each representation vertically.

Summary

In this short article, we discussed how we can solve the String Format problem on Hacker Rank. We solved the problem using three different methods and explained each of them.