Submission #734608

#	Time	Username	Problem	Language	Result	Execution time	Memory
734608		DAleksa	Brunhilda’s Birthday (BOI13_brunhilda)	C++17	97.78 / 100	507 ms	195040 KiB

brunhilda

#include <bits/stdc++.h>

using namespace std;

const int N = 1e7 + 10;
int n, q;
vector<int> p;
vector<int> v;
int cnt[N];
int prime[N];
int prv[N];
int dp[N];

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> q;
    p.resize(n);
    for(int i = 0; i < n; i++) cin >> p[i];
    for(int i = p.size() - 1; i >= 0; i--) {
        for(int j = p[i]; j < N; j += p[i]) {
            if(prime[j] == 0) {
                cnt[j]++;
                prime[j] = p[i];
            }
        }
    }
    cnt[0]++;
    prime[0] = p.back();
    for(int i = 0; i < N; i++) for(int j = 0; j < cnt[i]; j++) v.push_back(i);
    int j = 0;
    for(int i = 1; i < N; i++) {
        while(v[j] + prime[v[j]] <= i) j++;
        prv[i] = v[j];
    }
    for(int i = 1; i < N; i++) {
        if(prv[i] == i) dp[i] = -1;
        else dp[i] = dp[prv[i]] + 1;
    }
    while(q--) {
        int x;
        cin >> x;
        if(dp[x] == -1) cout << "oo\n";
        else cout << dp[x] << "\n";
    }
    return 0;
}

• Subtask 1: 17.77777777777778 / 20
• Subtask 2: 20 / 20
• Subtask 3: 60 / 60