ne_viens
Advanced Member | Редактировать | Профиль | Сообщение | Цитировать | Сообщить модератору
[code]
import java.util.Comparator;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.Collections;
class Premul
{
int a;
int b;
double mul;
}
class GearSet
{
int a;
int b;
int c;
int d;
double delta;
double ratio;
GearSet(int a, int b, int c, int d, double delta, double ratio)
{
this.a = a;
this.b = b;
this.c = c;
this.d = d;
this.delta = delta;
this.ratio = ratio;
}
@Override
public String toString()
{
return String.format("%.5f", delta) + "%,\t" +
Integer.toString(a) + "/" + Integer.toString(b) + ",\t" +
Integer.toString(c) + "/" + Integer.toString(d);
}
}
class SortGears implements Comparator<GearSet>
{
public int compare(GearSet a, GearSet b)
{
if(a.delta > b.delta)
return 1;
if(a.delta < b.delta)
return -1;
return 0;
}
}
class SortMul implements Comparator<Premul>
{
public int compare(Premul a, Premul b)
{
if(a.mul > b.mul)
return 1;
if(a.mul < b.mul)
return -1;
return 0;
}
}
class GearCalc
{
private Premul[] pm;
GearCalc(String s)
{
String[] arr = s.split(",");
int len = arr.length;
int[] gears = new int[len];
for(int i = 0; i < len; ++i)
gears[i] = Integer.parseInt(arr[i]);
pm = new Premul[len * len];
for(int j = 0; j < len; ++j)
{
for(int i = 0; i < len; ++i)
{
pm[i + j * len] = new Premul();
pm[i + j * len].a = gears[j];
pm[i + j * len].b = gears[i];
pm[i + j * len].mul = gears[j] * gears[i];
}
}
Arrays.sort(pm, new SortMul());
}
ArrayList<GearSet> calc(double u, double precision)
{
ArrayList<GearSet> gs = new ArrayList<>();
for(int j = 0; j < pm.length; ++j)
{
double x = pm[j].mul / u;
int i = vlookup(x);
for( ; i < pm.length; ++i)
{
double ratio = pm[j].mul / pm[i].mul;
double delta = ratio / u - 1.;
delta = delta < 0. ? 0. - delta : delta;
if(delta < precision * 0.01)
{
gs.add(new GearSet(pm[j].b, pm[i].b, pm[j].a, pm[i].a, delta * 100, ratio));
}
if(pm[i].mul > x)
break;
}
}
Collections.sort(gs, new SortGears());
return gs;
}
private int vlookup(double x) //finds an index of next-lowest mul value
{
int lo = 0;
int hi = pm.length - 1;
int i = hi / 2;
while(hi >= lo)
{
if(this.pm[i].mul < x)
lo = i + 1;
else
hi = i - 1;
i = (hi + lo) / 2;
}
return i;
}
}
public class calc
{
public static void main(String[] args)
{
String s = "20,20,23,24,25,25,30,33,34,35,37,40,41,43,45,47,48,50,53,55,57,58,59,60,61,62,65,67,70,71,73,75,79,80,83,85,89,90,92,95,97,98,100";
long start = System.nanoTime();
GearCalc gc = new GearCalc(s);
ArrayList<GearSet> gs = gc.calc(0.184584124, 0.01);
System.out.println("Execution time: " + (double)(System.nanoTime() - start) / 1000000. + "ms\n");
for(int i = 0; i < gs.size(); ++i)
{
System.out.println(gs.get(i));
}
}
}
[/code] |
