Vals geld

gistfile1.java

package valsgeld;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Scanner;
import java.util.TreeSet;

// spaces instead of tabs.


public class Main {


    public static void main(String[] args){
        int n, length; // separate lines is better
        String[] weging;
        List<String[]> geldpakket;
        List<List<String[]>> lijstVanPakketten;
        Scanner input = new Scanner(System.in);
        StringBuffer evenwicht, zwaarder, lichter;

        // Try to use interfaces rather than fixed classes. That way, you are always safe, as long as there's something that implements this interface.
        // You were doing that with List afaik.
        TreeSet<Character> result = new TreeSet<Character>();
        boolean licht = false, zwaar = false; // Put these on two separate lines.

        n = input.nextInt();
        lijstVanPakketten = new ArrayList<List<String[]>>(n); // Just a simple array suffices, you're indexing anyway.

        for(int i=0;i<n;i++){ // spaces around operators and after ;
            length = input.nextInt();
            geldpakket = new ArrayList<String[]>(length); // Just a simple array suffices, I think, since you know the length/size.
            for(int j=0;j<length;j++){
                weging = new String[3];
                for(int k=0;k<3;k++){
                    weging[k] = input.next();
                }
                geldpakket.add(weging);
            }
            lijstVanPakketten.add(geldpakket); // This looks odd, given that you give it a fixed size above
        }

        for(int i=0;i<lijstVanPakketten.size();i++){
            // implement the below in a separate method. You call that method per case. Makes it more clear what is going on
            // also call it something else, lijstVanPakketten seems awkward, since it's not really true, it's lijstvanlijstvanpakketten
            evenwicht = new StringBuffer();
            lichter = new StringBuffer();
            zwaarder = new StringBuffer();
            for(int j=0;j<lijstVanPakketten.get(i).size();j++){
                if(lijstVanPakketten.get(i).get(j)[2].equals("evenwicht")) {
                    evenwicht.append(lijstVanPakketten.get(i).get(j)[0]); // write a separate method that does the get(i).get(j), see blood example
                    evenwicht.append(lijstVanPakketten.get(i).get(j)[1]);
                }
                if(lijstVanPakketten.get(i).get(j)[2].equals("omhoog")) {
                    zwaarder.append(lijstVanPakketten.get(i).get(j)[0]);
                    lichter.append(lijstVanPakketten.get(i).get(j)[1]);
                }
                if(lijstVanPakketten.get(i).get(j)[2].equals("omlaag")) {
                    zwaarder.append(lijstVanPakketten.get(i).get(j)[1]);
                    lichter.append(lijstVanPakketten.get(i).get(j)[0]);
                }
            }

            if(evenwicht.length()!=0){
                String s = evenwicht.toString();
                if(lichter.length()!=0)
                    for(int k=0;k<lichter.length();k++){
                        if(s.indexOf(lichter.charAt(k))==-1) {
                            result.add(lichter.charAt(k));
                            licht = true;
                        }
                        if(s.indexOf(zwaarder.charAt(k))==-1) {
                            result.add(zwaarder.charAt(k));
                            zwaar = true;
                        }
                    }
            }
            else {
                //System.out.println("leeg evenwichtsbuffer");
                // The below is confusing :-)
                Map<Character, Integer> map = new HashMap<Character, Integer>();
                //controleer stringbuffer lichter
                for(int j=0;j<lichter.length();j++){
                    if(!map.containsKey(lichter.charAt(j))) map.put(lichter.charAt(j), 1);
                    else {map.put(lichter.charAt(j), map.get(lichter.charAt(j))+1);}
                }
                //controleer stringbuffer zwaarder
                for(int j=0;j<zwaarder.length();j++){
                    if(!map.containsKey(zwaarder.charAt(j))) map.put(zwaarder.charAt(j), 1);
                    else {map.put(zwaarder.charAt(j), map.get(zwaarder.charAt(j))+1);}
                }
                Collection c = map.values();
                int max = Collections.max(c);
                for(int j=0;j<zwaarder.length();j++){
                    if(map.get(zwaarder.charAt(j)) == max){
                        result.add(zwaarder.charAt(j));
                        zwaar=true;
                    }
                    if(map.get(lichter.charAt(j)) == max){
                        result.add(lichter.charAt(j));
                        licht=true;
                    }
                }
            }
            if(result.size() == 1 && licht != zwaar){
                if(licht) System.out.println("Het valse geldstuk " +result.first()+ " is lichter.");
                else System.out.println("Het valse geldstuk " +result.first()+ " is zwaarder.");
            }
            else if(lijstVanPakketten.get(i).size() == 1 || zwaar != licht) System.out.println("Te weinig gegevens.");
            else System.out.println("Inconsistente gegevens.");

            result.clear();
            licht = false;
            zwaar = false;
        }
    }
}