Problem
A number with k digits is an Armstrong number if the sum of each digit raised to the power k equals the number. For example 153 = 1³ + 5³ + 3³.
Implement is_armstrong(n).
Input
n: A non-negative integer.
Output
Return true if n is an Armstrong number.
Constraints
0 ≤ n ≤ 10¹⁸
Examples
Example 1
Input:
n = 153
Expected output:
expected = True
Input:
long long n = 153;
Expected output:
bool expected = true;
Input:
long n = 153;
Expected output:
bool expected = true;
Explanation
1³ + 5³ + 3³ = 1 + 125 + 27 = 153.
Example 2
Input:
n = 10
Expected output:
expected = False
Input:
long long n = 10;
Expected output:
bool expected = false;
Input:
long n = 10;
Expected output:
bool expected = false;
Explanation
1² + 0² = 1, which is not 10.
References
This challenge is adapted for CodeUtility. Follow the statement and constraints above.