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package shared;
import java.io.File;
import java.util.Arrays;
import dna.Data;
import fileIO.ByteFile1;
import fileIO.TextFile;
import fileIO.TextStreamWriter;
import structures.LongList;
/**
* @author Brian Bushnell
* @date Oct 9, 2012
*
*/
public class Primes {
public static void main(String[] args){
if(args.length==3){makePrimes(args);}
else{
System.out.println(primeAtLeast(100));
System.out.println(primeAtLeast(1000));
System.out.println(primeAtLeast(10000));
System.out.println(primeAtLeast(100000));
System.out.println(primeAtLeast(1000000));
System.out.println(primeAtLeast(10000000));
System.out.println(primeAtLeast(100000000));
System.out.println(primeAtLeast(1000000000));
System.out.println(primeAtLeast(10000000000L));
System.out.println(primeAtLeast(100000000000L));
System.out.println(primeAtLeast(1000000000000L));
System.out.println(primeAtLeast(10000000000000L));
System.out.println(primeAtLeast(100000000000000L));
System.out.println(primeAtLeast(1000000000000000L));
System.out.println(primeAtMost(100));
System.out.println(primeAtMost(1000));
System.out.println(primeAtMost(10000));
System.out.println(primeAtMost(100000));
System.out.println(primeAtMost(1000000));
System.out.println(primeAtMost(10000000));
System.out.println(primeAtMost(100000000));
System.out.println(primeAtMost(1000000000));
System.out.println(primeAtMost(10000000000L));
System.out.println(primeAtMost(100000000000L));
System.out.println(primeAtMost(1000000000000L));
System.out.println(primeAtMost(10000000000000L));
System.out.println(primeAtMost(100000000000000L));
System.out.println(primeAtMost(1000000000000000L));
}
}
public static void makePrimes(String[] args){
String in=args[0];
String out=args[1];
double mult=Double.parseDouble(args[2]);
assert(mult>=1);
long next=1;
if(!new File(in).exists()){throw new RuntimeException("File not found: "+in);}
TextFile tf=new TextFile(in, true);
TextStreamWriter tsw=new TextStreamWriter(out, true, false, false);
tsw.start();
// int cnt=0;
for(String s=tf.nextLine(); s!=null; s=tf.nextLine()){
// cnt++;
// if(cnt>10000){break;}
long x=Long.parseLong(s.trim());
// System.out.println("cnt="+cnt+", x="+x+", next="+next);
if(x>=next){
tsw.print(x+"\n");
next=(long)(x*mult);
}
}
tsw.poison();
tf.close();
}
public static long primeAtLeast(long x){
int loc=Arrays.binarySearch(primes, x);
if(loc<0){
loc=-(loc+1);
assert(loc>=primes.length || primes[loc]>x) : x;
}
if(loc>=primes.length){//Out of bounds
long d=(long)Math.pow(x, 0.4);
long a=primeAtLeast(x/d);
long b=primeAtLeast(x/a);
long c=a*b;
assert(c>=x && c<(x*9)/8) : x+", "+a+", "+b+", "+c+", "+d;
return c;
}
while(primes[loc]<x){loc++;}
return primes[loc];
// for(long p : primes){
// if(p>=x){return p;}
// }
// throw new RuntimeException("No primes big enough for "+x);
}
public static int primeAtMost(int x){
return (int)primeAtMost((long)x);
}
public static long primeAtMost(final long x){
final int loc0=Arrays.binarySearch(primes, x);
int loc=loc0;
if(loc<0){
loc=-(loc+1);
assert(loc>=primes.length || primes[loc]>x) : x;
}
assert(loc>=0) : loc+", "+x;
if(loc>=primes.length){//Out of bounds
final long d=(long)Math.pow(x, 0.4);
final long a=primeAtMost(x/d);
final long b=primeAtMost(x/a);
final long c=a*b;
assert(c<=x && c>(x*7)/8) : x+", "+a+", "+b+", "+c+", "+d;
return c;
}
assert(loc>=0) : loc+", "+x;//-1, 0, -300302388, 2
assert(x>=primes[0]) : loc0+", "+loc+", "+x+", "+primes[0];
while(primes[loc]>x){loc--;}
return primes[loc];
// for(int i=primes.length-1; i>=0; i--){
// if(primes[i]<=x){return primes[i];}
// }
// throw new RuntimeException("No primes small enough for "+x);
}
// /**
// * @return
// */
// private static long[] fetchPrimes() {
// String fname=Data.findPath("?primes.txt.gz");
//
// TextFile tf=new TextFile(fname, false);
// String[] lines=tf.toStringLines();
// long[] array=new long[lines.length];
// for(int i=0; i<lines.length; i++){
// array[i]=Long.parseLong(lines[i].trim());
// }
// return array;
// }
private static long[] fetchPrimes() {
String fname=Data.findPath("?primes.txt.gz");
ByteFile1 tf=new ByteFile1(fname, false);
LongList list=new LongList();
for(byte[] line=tf.nextLine(); line!=null; line=tf.nextLine()){
list.add(Parse.parseLong(line));
}
return list.toArray();
}
public static final long[] primes=fetchPrimes();
}
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