Math Fundamentals18 sections · 814 units
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Largest Prime Factor - Implementation

The pseudocode

Here is the full solution:


function largestPrimeFactor(n)
    largestFactor := 1
    i := 2
    while i * i <= n
        while n mod i = 0
            largestFactor := i
            n := n / i
        i := i + 1
    if n > 1 then
        largestFactor := n
    return largestFactor

Time: O(n)O(\sqrt{n}). Space: O(1)O(1). The inner while loop divides out all occurrences of each prime factor before moving to the next.