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import java.util.Date;

public class NumberTest4 {

	static int max = 1000000;
	
	static int pc = 0;
	static double[] primesd = new double[max];
	static long[] primesl = new long[max];
	
	public static void main(String[] args) {

		long time = 0;
		
		long c = 5;
		double cd = c;
		double sqcd = Math.ceil(Math.sqrt(cd))+1;
		
		put(2.0d);
		put(3.0d);
		
		time = new Date().getTime();
		while(pc<max){
			boolean ip = true;
			for(int i=0; i<pc;i++){
				if(primesd[i]<sqcd){
					if(cd/primesd[i] == 0){
						ip = false;
						break;
					}
				}else{
					break;
				}
			}
			if(ip) put(cd);
			c+=2;
			cd = c;
			sqcd = Math.ceil(Math.sqrt(cd))+1;
		}
		
		System.out.println(new Date().getTime() - time);
		
		pc = 0;
		c = 5;
		long sqcl = (long)Math.ceil(Math.sqrt(cd))+1;
		
		put(2l);
		put(3l);
		
		time = new Date().getTime();
		while(pc<max){
			boolean ip = true;
			for(int i=0; i<pc;i++){
				if(primesl[i]<sqcl){
					if(cd/primesl[i] == 0){
						ip = false;
						break;
					}
				}else{
					break;
				}
			}
			if(ip) put(c);
			c+=2;
			sqcl = (long)Math.ceil(Math.sqrt(cd))+1;
		}
		
		System.out.println(new Date().getTime() - time);
		System.out.println("F");
		
	}
	
	static public void put(double d){
		primesd[pc++] = d;
	}
	
	static public void put(long d){
		primesl[pc++] = d;
	}

}