(UVA) The Grand Dinner - Solution

Link to the problem: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=1190

The solution below used a Greedy approach to solve this problem.

More details about this solution can be found in the code below through the comments.


import java.io.*;
import java.util.*;

class Main {
    public void process() throws NumberFormatException, IOException {
        Scanner sc = new Scanner(System.in);
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        int numTeams = sc.nextInt();
        int numTables = sc.nextInt();
        while (numTeams != 0 || numTables != 0) {
            Team[] teams = new Team[numTeams];
            Table[] tables = new Table[numTables];
           
            for (int i = 0; i < numTeams; i++) {
                teams[i] = new Team(i, sc.nextInt());
            }
            for (int i = 0; i < numTables; i++) {
                tables[i] = new Table(i, sc.nextInt());
            }
            Arrays.sort(teams); // sort in descending order
            Arrays.sort(tables); // sort in descending order
           
            ArrayList<TreeSet<Integer>> distribution = new ArrayList<>();
            for (int i = 0; i < numTeams; i++) {
                distribution.add(new TreeSet<Integer>());
            }
           
            // for each team, try to place everyone in an available table
            boolean everyone = true;
            for (int i = 0; i < numTeams; i++) {
                int sizeTeam = teams[i].numPeople; // if there are x people in a team, it is necessary at least x available tables
                for (int j = 0; j < numTables && teams[i].numPeople > 0; j++) {
                    // there is not any available table
                    if (tables[j].capacity == 0) {
                        continue;
                    }
                    distribution.get(teams[i].idTeam).add(tables[j].idTable+1);
                    teams[i].numPeople--;
                    tables[j].capacity--;
                }
                if (teams[i].numPeople > 0) {
                    everyone = false;
                    break;
                }
            }
           
            if (!everyone) {
                bw.write("0\n");
            } else {
                bw.write("1\n");
                for (int i = 0; i < numTeams; i++) {
                    for (Integer j : distribution.get(i)) {
                        bw.write(j+" ");
                    }
                    bw.write("\n");
                }
            }
           
            numTeams = sc.nextInt();
            numTables = sc.nextInt();
        }
                                                      
        bw.flush();
        bw.close();
       
        return;
    }
   
    public static void main(String[] args) throws NumberFormatException, IOException {
        Main m = new Main();
        m.process();
       
        System.exit(0);
    }
}

class Team implements Comparable<Team> {
    int idTeam;
    int numPeople;
   
    public Team(int id, int num) {
        idTeam = id;
        numPeople = num;
    }
   
    public int compareTo(Team t) {
        return t.numPeople-this.numPeople;
    }
}

class Table implements Comparable<Table> {
    int idTable;
    int capacity;
   
    public Table(int id, int c) {
        idTable = id;
        capacity = c;
    }
   
    public int compareTo(Table t) {
        return t.capacity-this.capacity;
    }
}