dsa · easy
Perfect Number
A **perfect number** equals the sum of its positive divisors excluding itself. 6 is perfect because 1 + 2 + 3 = 6. 1 is not (it has no proper divisor other than the empty sum 0).
Arguments
num— positive integer to test for perfection
Return whether num is perfect.
Example
num = 28. Divisors excluding itself: 1, 2, 4, 7, 14. Sum 28 → true.
num = 7 is prime, so the only proper divisor is 1 → false.
Constraints
1 <= num <= 10^8
Examples
Example 1
Input: 28 Expected: true
Example 2
Input: 7 Expected: false