Given an array of integers, sum the divisors of each number that has exactly four positive divisors.
Problem
You are given an integer array nums. For every number in the array, determine whether it has exactly four positive divisors.
If a number has exactly four positive divisors, add the sum of those divisors to the final answer. Otherwise, ignore that number.
Return the total sum over all qualifying numbers.
A positive divisor of n is a positive integer that divides n evenly.
Goal
Compute the sum of divisors for all values in nums that have exactly four divisors.
Input Format
- An integer array
nums. - Each element represents a positive integer.
Output Format
- Return an integer: the sum of the divisors of every array element that has exactly four positive divisors.
Constraints
1 <= nums.lengthis assumed to be small enough for per-number divisor checks.- Each
nums[i]is a positive integer. - If a number does not have exactly four divisors, it contributes
0to the result.
Example 1
Input
nums = [21, 4, 7]
Output
32
Explanation
- 21 has divisors [1, 3, 7, 21], so it qualifies and contributes 32.
- 4 has divisors [1, 2, 4], so it is ignored.
- 7 has divisors [1, 7], so it is ignored.
Total = 32.
Example 2
Input
nums = [10, 6, 8]
Output
18
Explanation
- 10 has divisors [1, 2, 5, 10], sum = 18.
- 6 has divisors [1, 2, 3, 6], sum = 12.
- 8 has divisors [1, 2, 4, 8], sum = 15.
Each of these has exactly four divisors, so the total is 18 + 12 + 15 = 45.
Note: if you want a strict one-answer example, use only one qualifying value.
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