在Codeforces问题797A上获取运行时错误

Question

我目前正在Codeforces中尝试出现问题。每当我在计算机上运行程序时，它就会完美运行。但是，当我提交以下代码时，第一个测试用例出现错误。我尝试将变量的类型从“ long long”更改为“ signed int”，但是，我一直遇到相同的错误。我该如何解决这个问题？

测试用例

100000 2

错误消息

Diagnostics detected issues [cpp.clang++-diagnose]: p71.cpp:20:16: runtime error: signed integer overflow: 46349 * 46349 cannot be represented in type 'long'
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior p71.cpp:20:16 in

代码

#include <iostream>
#include <vector>
#include <bitset>
#define ll long long

using namespace std;

bitset<110001> b;
vector<ll> primes;
vector<ll> factors;

void sieve() {

    b.set();

    for(long i=2;i<110001;i++) {

        if(b[i]) {

            for(long j=i*i;j<110001;j+=i) {

                b[j] = 0;
            }

            primes.push_back(i);
        }
    }
}

void prime_factors(ll n) {

    sieve();

    vector<ll>::iterator it = primes.begin();
    ll pf = (*it);
    ll num = n;
    ll divisor_count = 1;
    ll power;

    while(pf <= n) {

        while(num%pf == 0) {
            num = num/pf;
            factors.push_back(pf);
        }

        it++;
        pf = (*it);
    }
}

int main() {

    ll n,k;
    cin>>n;
    cin>>k;

    prime_factors(n);

    if(factors.size() < k) {
        cout<<-1;
    }
    else {

        ll i;

        for(i=0;i<k-1;i++) {
            cout<<factors.at(i)<<" ";
        }

        ll last = 1;

        for(ll j=i;j<factors.size();j++) {
            last = last*factors.at(j);
        }

        cout<<last;
    }

    return 0;
}