Submission

Score: 100

User: njoop

Problemset: Twin, Cousin, and Sexy Prime

Language: cpp

Time: 0.529 second

Submitted On: 2025-05-25 16:23:21

#include <iostream>
#include <vector>
using namespace std;
int main()
{
    vector <bool> prime(100000020,true);
    int twin=0,cousin=0,sexy=0,l,u,i,j;
    prime[0] = prime[1] = false;
    cin >> l >> u;
    for (i=2;i<u;i++)
        if (prime[i])
        {
            for (j=2*i;j<=u+6;j+=i) prime[j]=false;
            if (i>=l)
            {
                if (prime[i-2]||prime[i+2]) twin++;
                if (i==3 || ((i>4 && prime[i-4])||prime[i+4])) cousin++;
                if (i==5 || ((i>6 && prime[i-6])||prime[i+6])) sexy++;
            }
        }
    cout << twin << endl << cousin << endl << sexy;
    return 0;
}