Submission

Score: 0

User: colo39

Problemset: Twin, Cousin, and Sexy Prime

Language: cpp

Time: 0.000 second

Submitted On: 2026-10-02 22:12:49

#include <bits/stdc++.h>
using namespace std;
int lp[70000005];

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int l,u, n;
    cin >> l >> u;
    n = u+10;
    set<int
    vector<int> primes;
    vector<bool> primess(n+10,0);
    for (int i = 2;i <= n;i++) {
        if (lp[i] == 0) {
            primes.push_back(i);
            lp[i] = i;
            primes[i]=1;
        }
        for (int p : primes) {
            if (p > lp[i] || 1LL * i * p > n) break;

            lp[i*p] = p;
        }
    }
    set<int> twin_p;
    set<int> cousin_p;
    set<int> sexy_p;
    for (int i = l;i <= u;i++) {
        if (primess[i]) {
            if (primess[i]) {
                if (primess[i+2]) {
                    if (i >= a) {
                        twin_p.insert(i);
                    }
                    if (i+2 <= b and i+2 >= a) {
                        twin_p.insert(i+2);
                    }
                }
                if (primess[i+4]) {
                    if (i >= a) {
                        cousin_p.insert(i);
                    }
                    if (i+4 <= b and i + 4 >= a) {
                        cousin_p.insert(i+4);
                    }
                }
                if (primess[i+6]) {
                    if (i >= a) {
                        sexy_p.insert(i);
                    }
                    if (i + 6 <= b and i + 6 >= a) {
                        sexy_p.insert(i+6);
                    }
                }
            }
        }

    }
    cout << twin_p.size() << "\n";
    cout << cousin_p.size() << "\n";
    cout << sexy_p.size() << "\n";
}