Minimization of while loop in Armstrong Numbers (TheAlgorithms#9976)

* Minimization of while loop in Armstrong Numbers

The while loop is removed and simple length calculation is used so the task of minimization of while loop is achieved

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: 2 people

Diff for: maths/armstrong_numbers.py

@@ -29,9 +29,7 @@ def armstrong_number(n: int) -> bool:
     number_of_digits = 0
     temp = n
     # Calculation of digits of the number
-    while temp > 0:
-        number_of_digits += 1
-        temp //= 10
+    number_of_digits = len(str(n))
     # Dividing number into separate digits and find Armstrong number
     temp = n
     while temp > 0: