package polinoms;
import java.util.Vector;

public class Polinom implements Cloneable {
	
	private int degree;
	private Vector<Number> coef = null;
		
	public Polinom (Number [] array) {
		degree = array.length-1;
		coef = new Vector<Number>(array.length);
		for(int i=0; i<array.length; i++)
			coef.add(array[i]);
	}
	
	public Polinom (Polinom p) {  // Copy constructor
		degree = p.degree;
		coef = (Vector<Number>)p.coef.clone();
	}
	
	public Polinom (Vector<Number> v) {
		degree = v.size();
		coef = (Vector<Number>)v.clone();
	}
	
	private Polinom (int degree) {
		this.degree = degree;
		coef = new Vector<Number>(degree+1);	
		for(int i=0; i<=degree; i++)
			coef.add(0);
	}
	
	public Number value(Number x) {
		double result = coef.elementAt(degree).doubleValue();
		double dx = x.doubleValue();
		for(int i=degree-1; i>=0; i--) {
			result = result * dx + coef.elementAt(i).doubleValue();
		}
		return new Double(result);
	}

	public Polinom add(Polinom other) {
		Polinom result;
		Polinom second;
		if(this.degree >= other.degree) {
			result = new Polinom(this);
			second = other;
		}
		else {
			result = new Polinom(other);
			second = this;
		}
		double d;
		for(int i=0; i<=second.degree; i++) {
			d = result.coef.elementAt(i).doubleValue() + second.coef.elementAt(i).doubleValue();
			coef.set(i, d);
		}
		return result;
	}
	
	public Polinom mult(Polinom other) {
		Polinom result = new Polinom(this.degree+other.degree);
		double d;
		for(int i=0; i<=this.degree; i++)
			for(int j=0; j<=other.degree; j++) {
				d = result.coef.elementAt(i+j).doubleValue() + 
					this.coef.elementAt(i).doubleValue() * other.coef.elementAt(j).doubleValue();
				result.coef.setElementAt(d, i+j);
			}
		return result;
	}
	
	public boolean equals(Object o) {
		if(o == null)
			return false;
		if(!(o instanceof Polinom))
			return false;
		if(o == this)
			return true;
		Polinom tmp = (Polinom)o;
		return degree == tmp.degree && coef.equals(tmp.coef);
	}
	
	public Object clone() {
		Polinom result = null;
		try {
			result = (Polinom) super.clone();
		} catch (CloneNotSupportedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		result.coef = (Vector<Number>) coef.clone();
		return result;
	}
	
	public String toString() {
		StringBuffer str = new StringBuffer("");
		for(int i=degree; i>0; i--) {
			str.append(coef.elementAt(i) + "*x^" + i + " + ");
		}
		str.append(coef.elementAt(0));
		return str.toString();
	}
}