Submission #447944

#	Time	Username	Problem	Language	Result	Execution time	Memory
447944		prvocislo	Brunhilda’s Birthday (BOI13_brunhilda)	C++17	100 / 100	888 ms	123724 KiB

brunhilda

#include <bits/stdc++.h>
typedef long long ll;
using namespace std;

const int maxn = 1e7 + 5, inf = 1e9 + 5;
void chmin(int &a, const int &b) { a = min(a, b); }
void chmax(int &a, const int &b) { a = max(a, b); }
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    vector<int> lp(maxn, -1), pr;
    for (int i = 2; i < maxn; i++)
    {
        if (lp[i] == -1) pr.push_back(i), lp[i] = i;
        for (int j = 0; j < pr.size() && pr[j] <= lp[i] && i * pr[j] < maxn; j++) 
            lp[i*pr[j]] = pr[j];
    }
    int m, q;
    cin >> m >> q;
    vector<int> p(m);
    vector<bool> b(maxn, false);
    int mul = 1;
    for (int i = 0; i < m; i++)
    {
        cin >> p[i];
        if (mul * 1ll * p[i] < (ll)maxn) mul *= p[i];
        else mul = maxn;
        b[p[i]] = true;
    }
    vector<int> dp(maxn, inf), hr(maxn+1, 0);
    for (int i = 0; i < mul; i++)
    {
        if (!i) dp[i] = 0;
        else
        {
            if (i <= hr[dp[i-1]]) dp[i] = dp[i-1];
            else dp[i] = dp[i-1]+1;
        }
        int big = 1;
        if (!i) big = p.back();
        for (int j = i; j > 1; j /= lp[j])
            if (b[lp[j]]) chmax(big, lp[j]);
        if (big != 1)
        {
            chmax(hr[dp[i]+1], i+big-1);
        }
    }
    while (q--)
    {
        int n; cin >> n;
        if (dp[n] == inf) cout << "oo\n";
        else cout << dp[n] << "\n";
    }
    return 0;
}

Compilation message (stderr)

brunhilda.cpp: In function 'int main()':
brunhilda.cpp:16:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |         for (int j = 0; j < pr.size() && pr[j] <= lp[i] && i * pr[j] < maxn; j++)
      |                         ~~^~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 60 / 60