When an input number is given as input. The input digit should be read and nearest cubic root value will be displayed as output

Question

For example:

Input = 21

Nearest cubic root values for above digit are: 2 and 3

• 8 = 2*2*2
• 27 = 3*3*3

Among those values, 27 is nearer to 3, so it should be displayed as output.

Answer 1

I believe you are mixing up digit with number. Digits are just 0-9. Having said that, from the description you are giving I believe you want to compute the smallest difference between a given number (e.g. 21) and the cubed values of the closest two integer values to the cubic root of said number.

So for 21 it would be:

• Cubic root = 21 ** (1/3) ~ 2,75
• Two closest integers:
  • 2
  • 3
• Their cubed values
  • 2 ** 3 = 8
  • 3 ** 3 = 27
• Difference to given number 21
  • | 8 - 21 | = 13
  • | 27 - 21 | = 6
• Smallest difference
  • 6 which is obtained when cubing 3 so print 3

Here a Python script that will do exactly that.

import sys


# helper function to check whether a string can be parsed as float
def represents_float(s):
    try:
        int(s)
        return True
    except ValueError:
        return False


# ask user to input a number
number_str = input("Please enter a number: ")
if not represents_float(number_str):
    print("You must enter a number")
    sys.exit(1)
number = float(number_str)

# calculate cubic root
cubic_root = number ** (1/3)

# get closest int values
smaller = int(cubic_root)
bigger = smaller + 1

# calculate difference
smaller_diff = abs(smaller ** 3 - number)
bigger_diff = abs(bigger ** 3 - number)

# print the one with smaller difference
if smaller_diff < bigger_diff:
    print(smaller)
else:
    print(bigger)

Expected output (if entering 21)

Please enter a number: 21
3