[PAT-A] 1096 Consecutive Factors

Java

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        sc.close();

        List<Integer> res = new ArrayList<>();
        for (int i = 2; i <= n / i; i++) {
            if (n % i == 0) {
                List<Integer> seq = new ArrayList<>();
                for (int m = n, j = i; m % j == 0; j++) {
                    seq.add(j);
                    m /= j;
                }

                if (seq.size() > res.size()) {
                    res = seq;
                }
            }
        }

        if (res.isEmpty()) {
            res.add(n);
        }

        System.out.println(res.size());
        System.out.print(res.get(0));
        for (int i = 1; i < res.size(); i++) {
            System.out.print("*" + res.get(i));
        }
    }
}

C++

#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>

using namespace std;

int n;

int main() {
    cin >> n;

    vector<int> res;
    for (int i = 2; i <= n / i; i++)
        if (n % i == 0) {
            vector<int> seq;
            for (int m = n, j = i; m % j == 0; j++) {
                seq.push_back(j);
                m /= j;
            }

            if (seq.size() > res.size()) res = seq;
        }

    if (res.empty()) res.push_back(n);

    cout << res.size() << endl;
    cout << res[0];
    for (int i = 1; i < res.size(); i++) cout << '*' << res[i];

    return 0;
}