Print all Disarium numbers within given range in Python

In this tutorial, we will learn to print all Disarium numbers within the given range using Python. Here we will learn what is a Disarium number, how to find whether a number is a Disarium number or not, and also a Python program to implement the same. If you want to get the Python program to print all the Disarium numbers within a given range, you are at the right place.

What is a Disarium number?

If the sum of the individual digits of a number raised to the power of its position equals the number, then it is a Disarium number. To understand what a Disarium number is, we will take an example-

• Suppose, the number is 135. Here, the positions of digits 1, 3, and 5 are 1, 2, and 3 respectively.
  So, 1^1 + 3^2 + 5^3 = 1 + 9 + 125 = 135
  So, the result is equal to the number we have taken. Therefore, the number 135 is a Disarium number.

Let us take another example for a better understanding of the above concept.

• Suppose, the number is 130. Here, the positions of digits 1, 3, and 0 are 1, 2, and 3 respectively.
  So, 1^1 + 3^2 + 0^3 = 1 + 9 + 0 = 10
  So, the result is not equal to the number we have taken. Therefore, the number 130 is not a Disarium number.

Method to find if a number is a Disarium number

So, we will learn to check whether a number is a Disarium number or not. We can check if a number is a Disarium number by following the steps given below-

• Steps to calculate the number of digits in the number-
• Divide the number by 10.
• Increment the digit count by 1.
• Steps to check whether the number is a Disarium number-
• Declare a variable to store the sum.
• Calculate the remainder after dividing the number by 10.
• Multiply the remainder by the number of digits.
• Add the result to the sum.
• Divide the number by 10.
• Decrement the number of digits by 1.
• Check if the sum is equal to the number.
• If the comparison results true, the number is a Disarium number.
• Otherwise, the number is not a Disarium number.

Python program to print all Disarium numbers within the given range

Now, we will see a Python program to display Disarium numbers within the range. Here, we will take the lower and upper bound of the range from the user. Using a ‘for’ loop, we traverse from lower bound to upper bound and check whether the number is a Disarium number or not. The Python program is as follows-

def check_disarium(number):    
  no_digits = 0
  num = number	
  while(num != 0):
    no_digits = no_digits + 1
    num = num//10

  remainder = 0
  disarium_num = 0    
  while(number > 0):
    remainder = number % 10
    disarium_num = disarium_num + (remainder**no_digits)
    number = number//10
    no_digits = no_digits - 1
  return disarium_num

lower = int(input("ENTER LOWEST NUMBER : "))
upper = int(input("ENTER HIGHEST NUMBER : "))
print("DISARIUM NUMBERS WITHIN RANGE({},{}) ARE -".format(lower,upper))
for i in range(lower,upper+1):    
  if check_disarium(i) == i:
    print(i,end=" ")

Python program output

The above Python program prints Disarium numbers within the range given by the user. The output of the program is-

[email protected]:~/python$ python3 disarium.py
ENTER LOWEST NUMBER : 1
ENTER HIGHEST NUMBER : 200
DISARIUM NUMBERS WITHIN RANGE(1,200) ARE -
1 2 3 4 5 6 7 8 9 89 135 175 
[email protected]:~/python$

In this sample execution, the lower and upper bound entered by the user is 1 and 200 respectively. So, in the range (1, 200), there are 12 Disarium numbers- 1, 2, 3, 4, 5, 6, 7, 8, 9, 89, 135, 175.

Also read: Print all the peaks and troughs in a list of Integers in Python