10394 Twin Primes-02AfqLMq.txt

#include<iostream>
#include<cmath>
#include<cstdio>
#define MAX 18409210
using namespace std;
char prime[MAX]={0};
void primeGenerator(long long int n )
{
    int x = sqrt( n );
    prime[0] = prime[1] = 1;
    for( int i = 4; i <= n; i += 2 )
        prime[i] = 1;
    for( int i = 3; i <= x; i += 2 ) {
        if( prime[i] == 0 ) {
            for( int j = i+i; j <= n; j += i ){
                prime[j] = 1;
            }
        }
    }
    return;
}

int main()
{
    primeGenerator(18409210);
    long long int i;int t=1;int twin[100002];
    for(int p=3; p<=MAX; p+=2){
        if(prime[p]==0 && prime[p+2]==0)
            twin[t++]=p;
    }
    while(scanf("%lld",&i)!=EOF){
        if(i<=0 || i>100000)
            printf("(%d, %d)\n",0,0);
        else
            printf("(%d, %d)\n",twin[i],twin[i]+2);
    }
    return 0;
}