NumberTheory/Math/Factorization.h

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• Last update: 2025-06-11 15:37:14+07:00

Depends on

• template.h

Verified with

• NumberTheory/Math/test/aizu_ntl_1_a_prime_factor.test.cpp

Code

#include "../../template.h"


vector<ll> primeFactor(ll n) {
    vector<ll> factor;
    for (int i : {2, 3, 5}) {
        while (n % i == 0) {
            n /= i;
            factor.push_back(i);
        }
    }
    int inc[] = {4, 2, 4, 2, 4, 6, 2, 6};
    int j = 0;
    for (ll i = 7; i * i <= n; i += inc[j%8], j++) {
        while(n % i == 0) {
            n /= i;
            factor.push_back(i);
        }
    }
    if (n > 1) factor.push_back(n);
    return factor;
}

#line 2 "template.h"

#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define MOD (ll)(1e9+7)
#define all(x) (x).begin(),(x).end()
#define unique(x) x.erase(unique(all(x)), x.end())
#define INF32 ((1ull<<31)-1)
#define INF64 ((1ull<<63)-1)
#define inf (ll)1e18

#define vi vector<int>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second

const int mod = 998244353;

void solve();

int main(){
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    // cin.exceptions(cin.failbit);
    // int t; cin >> t;
    // while(t--)
        solve();
    cerr << "\nTime run: " << 1000 * clock() / CLOCKS_PER_SEC << "ms" << '\n';
    return 0;
}
#line 2 "NumberTheory/Math/Factorization.h"


vector<ll> primeFactor(ll n) {
    vector<ll> factor;
    for (int i : {2, 3, 5}) {
        while (n % i == 0) {
            n /= i;
            factor.push_back(i);
        }
    }
    int inc[] = {4, 2, 4, 2, 4, 6, 2, 6};
    int j = 0;
    for (ll i = 7; i * i <= n; i += inc[j%8], j++) {
        while(n % i == 0) {
            n /= i;
            factor.push_back(i);
        }
    }
    if (n > 1) factor.push_back(n);
    return factor;
}

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