UVa 10394 - Twin Primes

	/**
	* Status : Accepted.
	* Author : ~menon.
	* Date: 30.03.2015
	*/
	#include <iostream>
	#include <cmath>
	#include <cstdio>
	#include <cstring>
	#define MAX 20000010
	int prime[MAX];
	int twinPrime[MAX];
	void sieve()
	{
	int i, j, n;
	memset(prime, 1, sizeof(prime));
	n = sqrt(MAX);
	for(i = 2; i <= n; i++) {
	if(prime[i]) {
	for(j = 2; i * j <= MAX; j++) {
	prime[i * j] = 0;
	}
	}
	}
	}
	void CalculateTwinPrime()
	{
	int i, j;
	j = 1;
	for(i = 2; i <= MAX; i++) {
	if(prime[i] && prime[i + 2]) {
	twinPrime[j++] = i;
	}
	}
	}
	int main()
	{
	int n;
	sieve();
	CalculateTwinPrime();
	while(scanf("%d", &n) != EOF)
	{
	printf("(%d, %d)\n", twinPrime[n], twinPrime[n] + 2);
	}
	return 0;
	}

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