Union Find Java

import java.util.Scanner;

public class UnionFind {

    static Scanner scan = new Scanner(System.in);
    final static int maxnodos = (int) (1e6+1);

    static int[] altura = new int[maxnodos+1];
    static int[] padre = new int[maxnodos+1];

    static void init()
    {
        for(int i = 1; i <= maxnodos; i++)
        {
            altura[i] = 1;
            padre[i] = i;
        }
    }

    static int find(int a)
    {
        int retValue = padre[a];
        if(padre[a] != a)
        {
            retValue = find(padre[a]);
        }
        padre[a] = retValue;
        return retValue;
    }

    static boolean check(int a , int b)
    {
        return find(a) == find(b);
    }

    static void union(int a, int b)
    {
        a = find(a);
        b = find(b);
        if(a == b) return;
        if(altura[b]> altura[a])
        {
            int t = b;
            b = a;
            a = t;
        }
        padre[b]= a;
        altura[a]+= altura[b];
    }

    public static void main(String[] args) {

        char x;
        int a, b;
        init();
        while((x= scan.next().charAt(0)) != 'F')
        {
            a = scan.nextInt();
            b = scan.nextInt();
            if(x == 'P') System.out.println(check(a, b) ? "S" : "N");
            else union(a, b);
        }

    }

}