Java

public class Pont{
    private int x;
    private int y;

    public Pont(int x, int y){
        this.x = x;
        this.y = y;
    }
}

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public class Pontok{
    private Pont[] pontok;

    public Pontok(){
        this.pont = new Pont[0];
    }

    public void pontHozzaAd(Pont pontxy){
        Pont[] ujPont = new Pont[pont.length+1];
                for(int i = 0; i<pont.length;i++){
                    ujPont[i] = pont[i];
                }
                ujPont[ujPont.length-1] = pontxy;
            pont = ujPont;
    }
}