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/* vim: set expandtab tabstop=4 shiftwidth=4 : */
import java.util.HashMap;
public class BaseballElimination
{
private static final boolean DEBUG = false;
private int n;
private String[] names;
private int[] wins;
private int[] losses;
private int[] remains;
private int[][] games;
private HashMap<String, Integer> nameToI;
private boolean[] eliminated;
private HashMap<Integer, Stack<String>> eliminatedBy;
public BaseballElimination(String filename)
{
In in = new In(filename);
n = in.readInt();
names = new String[n];
wins = new int[n];
losses = new int[n];
remains = new int[n];
games = new int[n][n];
nameToI = new HashMap<String, Integer>();
eliminated = new boolean[n];
eliminatedBy = new HashMap<Integer, Stack<String>>();
for (int i = 0; i < n; i++) {
names[i] = in.readString();
wins[i] = in.readInt();
losses[i] = in.readInt();
remains[i] = in.readInt();
for (int j = 0; j < n; j++) {
games[i][j] = in.readInt();
}
nameToI.put(names[i], i);
}
trivialEliminations();
for (int i = 0; i < n; i++) {
// if (!eliminated[i] && shouldBeEliminated(i)) {
if (!eliminated[i]) {
maxFlowComputation(i);
}
}
}
private void addEliminatedBy(int who, int by)
{
Stack<String> s = eliminatedBy.get(who);
if (s == null) {
s = new Stack<String>();
s.push(names[by]);
eliminatedBy.put(who, s);
} else {
s.push(names[by]);
}
}
private void trivialEliminations()
{
// even if the team wins all its remaining games
// it won't catch up with the best teams
for (int i = 0; i < n; i++) {
int w = wins[i] + remains[i];
for (int j = 0; j < n; j++) {
// (i == j) is safe
if (w < wins[j]) {
eliminated[i] = true;
addEliminatedBy(i, j);
}
}
}
}
private boolean shouldBeEliminated(int t)
{
// even if the team wins all its remaining games
// it won't catch up with the min of the others wins
int w = wins[t] + remains[t];
int ws = 0;
for (int i = 0; i < n; i++) {
if (i == t) continue;
ws += wins[i];
for (int j = i; j < n; j++) {
if (j == t) continue;
ws += games[i][j];
}
}
if (w < Math.ceil(ws / (float) (n-1))) {
return true;
}
return false;
}
private int countGamesWithout(int t)
{
int c = 0;
for (int i = 0; i < n; i++) {
if (i == t) continue;
for (int j = i; j < n; j++) {
if (j == t) continue;
if (games[i][j] > 0) c++;
}
}
return c;
}
private void maxFlowComputation(int t)
{
int g = countGamesWithout(t);
// s + t + games + teams
int vertices = 2 + g + n;
FlowNetwork flowNetwork = new FlowNetwork(vertices);
int S = vertices - 2;
int T = vertices - 1;
int idx = n;
int b = wins[t] + remains[t];
for (int i = 0; i < n; i++) {
if (i == t) continue;
// team -> T
FlowEdge e = new FlowEdge(i, T, (b - wins[i]));
flowNetwork.addEdge(e);
for (int j = i; j < n; j++) {
if (j == t) continue;
if (games[i][j] > 0) {
// S -> game
e = new FlowEdge(S, idx, games[i][j]);
flowNetwork.addEdge(e);
// game -> team i
e = (new FlowEdge(idx, i, Double.POSITIVE_INFINITY));
flowNetwork.addEdge(e);
// game -> team j
e = (new FlowEdge(idx, j, Double.POSITIVE_INFINITY));
flowNetwork.addEdge(e);
idx++;
}
}
}
if (DEBUG) {
System.out.println(names[t]+" should be out…");
System.out.println(flowNetwork.toString());
}
FordFulkerson maxFlow = new FordFulkerson(flowNetwork, S, T);
if (DEBUG) {
System.out.println(flowNetwork.toString());
System.out.printf("Team: %s got :%g \n", names[t], maxFlow.value());
}
boolean out = false;
for (FlowEdge e : flowNetwork.adj(S)) {
if (DEBUG) System.out.println(e);
if (e.flow() != e.capacity()) {
out = true;
break;
}
}
if (out) {
eliminated[t] = true;
for (int i = 0; i < n; i++) {
if (maxFlow.inCut(i) && !eliminated[i]) {
addEliminatedBy(t, i);
}
}
}
}
private int teamI(String team)
{
Object i = nameToI.get(team);
if (i == null)
throw new IllegalArgumentException(team);
return (int) i;
}
public int numberOfTeams()
{
return n;
}
public Iterable<String> teams()
{
return nameToI.keySet();
}
public int wins(String team)
{
return wins[teamI(team)];
}
public int losses(String team)
{
return losses[teamI(team)];
}
public int remaining(String team)
{
return remains[teamI(team)];
}
public int against(String team1, String team2)
{
return games[teamI(team1)][teamI(team2)];
}
public boolean isEliminated(String team)
{
return eliminated[teamI(team)];
}
public Iterable<String> certificateOfElimination(String team)
{
int t = teamI(team);
if (!eliminated[t])
return null;
else {
return eliminatedBy.get(t);
}
}
public static void main(String[] args) {
BaseballElimination division = new BaseballElimination(args[0]);
for (String team : division.teams()) {
if (division.isEliminated(team)) {
StdOut.print(team + " is eliminated by the subset R = { ");
for (String t : division.certificateOfElimination(team))
StdOut.print(t + " ");
StdOut.println("}");
}
else {
StdOut.println(team + " is not eliminated");
}
}
}
}
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