PrimeFactors.cpp

#include<iostream>
#include<algorithm>
#include<cmath>
#include<vector>
#include <string>
#include <sstream>
#include <climits>
#include<iomanip>
using namespace std;
vector<int> prime_factors(long n) {
    vector<int> factors;
    if (n < 2) {
        return factors;
    }
    while (n % 2 == 0) {
        factors.push_back(2);
        n /= 2;
    }
    for (long i = 3; i <= sqrt(n); i += 2) {
        while (n % i == 0) {
            factors.push_back(i);
            n /= i;
        }
    }
    if (n > 2) {
        factors.push_back(n);
    }
    return factors;
}
int main()
{
    prime_factors(3);
    return 0;
}
/*Description:
Prime Factors

Inspired by one of Uncle Bob's TDD Kata

Write a function that generates factors for a given number.

The function takes an integer as parameter and returns a list of integers (ObjC: array of NSNumbers representing integers). That list contains the prime factors in numerical sequence.
Examples

1  ==>  []
3  ==>  [3]
8  ==>  [2, 2, 2]
9  ==>  [3, 3]
12 ==>  [2, 2, 3]

Algorithms*/
//          ／＞　　フ
//　　　　　| 　n　n 彡
//　 　　　／`ミ＿xノ
//　　 　 /　　　 　 |
//　　　 /　 ヽ　　 ﾉ
//　 　 │　　|　|　|
//　／￣|　　 |　|　|
//　| (￣ヽ＿_ヽ_)__)
//　＼二つ
// ITS CAT FOR YOU