# Codility: CountFactors Solution

*Lesson 10 Prime and Composite Numbers*

## Approach

If number

a

is a divisor of n

, then n/a

is also a divisor.One of these two divisors is less than or equal to

sqrt(n)

.This could be proven by contradictory. Assume if that were not the case,

n

would be a product of two numbers greater than sqrt(n)

, which is impossible.## Implementation

1function solution(N) {2 let result = 03 let i = 14 while (i * i < N) {5 if (N % i === 0) {6 result += 27 }8 i++9 }10 if (i * i === N) {11 result++12 }1314 return result15}

## Comments

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## Tags

codility

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