Submission

Score: 0

User: mumumimi

Problemset: Twin, Cousin, and Sexy Prime

Language: cpp

Time: 0.003 second

Submitted On: 2026-10-01 21:41:12

#include <bits/stdc++.h>
using namespace std;
bool isprime(int n){
    if(n<=1) return false;
    if(n==2) return true;
    if(n%2==0) return false;
    for(int i=3;i*i<=n;i+=2){
        if(n%i==0) return false;
    }
    return true;
}
int main(){
    set<int> twin,cousin,sexy;
    vector<int> v;
    int l,u;cin >> l >> u;
    for(int i=l;i<=u;i++){
        if(isprime(i)){
            v.push_back(i);
        }
    }
    for(int i=0;i<v.size();i++){
        if(v[i]+2<=u&&isprime(v[i]+2)){
            twin.insert(v[i]);
            twin.insert(v[i]+2);
        }
        if(v[i]+4<=u&&isprime(v[i]+4)){
            cousin.insert(v[i]);
            cousin.insert(v[i]+4);
        }
        if(v[i]+6<=u&&isprime(v[i]+6)){
            sexy.insert(v[i]);
            sexy.insert(v[i]+6);
        }
    }
    cout << twin.size() << "\n";
    cout << cousin.size() << "\n";
    cout << sexy.size() << "\n";
}