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package org.opentripplanner.profile;
import com.beust.jcommander.internal.Lists;
import com.google.common.collect.HashMultimap;
import com.google.common.collect.Iterables;
import com.google.common.collect.Multimap;
import gnu.trove.iterator.TIntIntIterator;
import gnu.trove.iterator.TIntIterator;
import gnu.trove.iterator.TObjectIntIterator;
import gnu.trove.list.TIntList;
import gnu.trove.list.array.TIntArrayList;
import gnu.trove.map.TIntIntMap;
import gnu.trove.map.TIntObjectMap;
import gnu.trove.map.TObjectIntMap;
import gnu.trove.map.hash.TIntIntHashMap;
import gnu.trove.map.hash.TIntObjectHashMap;
import gnu.trove.map.hash.TObjectIntHashMap;
import org.opentripplanner.model.Stop;
import org.opentripplanner.analyst.SampleSet;
import org.opentripplanner.analyst.cluster.TaskStatistics;
import org.opentripplanner.analyst.scenario.AddTripPattern;
import org.opentripplanner.analyst.scenario.ConvertToFrequency;
import org.opentripplanner.analyst.scenario.Scenario;
import org.opentripplanner.analyst.scenario.TransferRule;
import org.opentripplanner.analyst.scenario.TripPatternFilter;
import org.opentripplanner.common.model.GenericLocation;
import org.opentripplanner.routing.algorithm.AStar;
import org.opentripplanner.routing.core.RoutingRequest;
import org.opentripplanner.routing.core.State;
import org.opentripplanner.routing.core.TraverseMode;
import org.opentripplanner.routing.edgetype.SimpleTransfer;
import org.opentripplanner.routing.edgetype.TripPattern;
import org.opentripplanner.routing.error.VertexNotFoundException;
import org.opentripplanner.routing.graph.Graph;
import org.opentripplanner.routing.graph.Vertex;
import org.opentripplanner.routing.spt.DominanceFunction;
import org.opentripplanner.routing.spt.ShortestPathTree;
import org.opentripplanner.routing.trippattern.FrequencyEntry;
import org.opentripplanner.routing.trippattern.TripTimes;
import org.opentripplanner.routing.vertextype.TransitStop;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.stream.Collectors;
public class RaptorWorkerData implements Serializable {
public static final Logger LOG = LoggerFactory.getLogger(RaptorWorkerData.class);
/** we use empty int arrays for various things, e.g. transfers from isolated stops. They're immutable so only use one */
public static final int[] EMPTY_INT_ARRAY = new int[0];
public final int nStops;
public final int nPatterns;
/** The number of targets (vertices or samples) */
public final int nTargets;
/** For every stop, one pair of ints (targetStopIndex, distanceMeters) for each transfer out of that stop. This uses 0-based stop indices that are specific to RaptorData */
public final List transfersForStop = new ArrayList<>();
/** A list of pattern indexes passing through each stop, again using Raptor indices. */
public final List patternsForStop = new ArrayList<>();
/** For each pattern, a 2D array of stoptimes for each trip on the pattern. */
public List timetablesForPattern = new ArrayList<>();
/** does this RaptorData have any scheduled trips? */
public boolean hasSchedules = false;
/** does this RaptorData have any frequency trips? */
public boolean hasFrequencies = false;
/**
* Map from stops that do not exist in the graph but only for the duration of this search to their stop indices in the RAPTOR data.
*/
public TObjectIntMap addedStops = new TObjectIntHashMap<>();
/** Some stops may have special transfer rules. They are stored here. */
public TIntObjectMap> transferRules = new TIntObjectHashMap<>();
/** The transfer rules to be applied in the absence of another transfer rule */
public List baseTransferRules = new ArrayList<>();
/** The boarding assumption used for initial vehicle boarding, and for when there is no transfer rule defined */
public RaptorWorkerTimetable.BoardingAssumption boardingAssumption;
/**
* For each stop, one pair of ints (targetID, distanceMeters) for each destination near that stop.
* For generic TimeSurfaces these are street intersections. They could be anything though since the worker doesn't
* care what the IDs stand for. For example, they could be point indexes in a pointset.
*/
public final List targetsForStop = new ArrayList<>();
/** The 0-based RAPTOR indices of each stop from their vertex IDs */
public transient final TIntIntMap indexForStop;
/** Optional debug data: the name of each stop. */
public transient final List stopNames = new ArrayList<>();
public transient final List patternNames = new ArrayList<>();
/** Create RaptorWorkerData for the given window and graph */
public RaptorWorkerData (Graph graph, TimeWindow window, ProfileRequest request, TaskStatistics ts) {
this(graph, window, request, null, ts);
}
public RaptorWorkerData (Graph graph, TimeWindow window, ProfileRequest request, SampleSet sampleSet) {
this(graph, window, request, sampleSet, new TaskStatistics());
}
public RaptorWorkerData (Graph graph, TimeWindow window, ProfileRequest request) {
this (graph, window, request, null, new TaskStatistics());
}
/** Create RaptorWorkerData to be used to build ResultSets directly without creating an intermediate SampleSet */
public RaptorWorkerData (Graph graph, TimeWindow window, ProfileRequest req, SampleSet sampleSet, TaskStatistics ts) {
Scenario scenario = req.scenario;
int totalPatterns = graph.index.patternForId.size();
int totalStops = graph.index.stopForId.size();
timetablesForPattern = new ArrayList(totalPatterns);
List patternForIndex = Lists.newArrayList(totalPatterns);
TObjectIntMap indexForPattern = new TObjectIntHashMap<>(totalPatterns, 0.75f, -1);
indexForStop = new TIntIntHashMap(totalStops, 0.75f, Integer.MIN_VALUE, -1);
TIntList stopForIndex = new TIntArrayList(totalStops, Integer.MIN_VALUE);
this.boardingAssumption = req.boardingAssumption;
ts.patternCount = 0;
ts.frequencyEntryCount = 0;
ts.frequencyTripCount = 0;
ts.scheduledTripCount = 0;
// first apply any filters that need to be applied to the entire schedule at once
Collection graphPatterns = graph.index.patternForId.values();
// convert scheduled trips to freuquencies as needed
if (scenario != null && scenario.modifications != null) {
Collection frequencies = scenario.modifications.stream()
.filter(m -> m instanceof ConvertToFrequency)
.map(m -> (ConvertToFrequency) m)
.collect(Collectors.toList());
if (!frequencies.isEmpty()) {
// apply the operations
List scheduled = graphPatterns.stream()
.flatMap(p -> p.scheduledTimetable.tripTimes.stream())
.collect(Collectors.toList());
List frequencyEntries = graphPatterns.stream()
.filter(p -> p.getSingleFrequencyEntry() != null)
.flatMap(p -> p.scheduledTimetable.frequencyEntries.stream())
.collect(Collectors.toList());
for (ConvertToFrequency c : frequencies) {
c.apply(frequencyEntries, scheduled, graph, window.servicesRunning, req.boardingAssumption);
scheduled = c.scheduledTrips;
frequencyEntries = c.frequencyEntries;
}
// aggregate the modified trips back into patterns
// this is so that the patterns have object references to the relevant schedules and frequency entries
// group by the original pattern - each entry is still associated with a trip
Multimap newScheduledPatterns = HashMultimap.create();
for (TripTimes tt : scheduled) {
newScheduledPatterns.put(graph.index.patternForTrip.get(tt.trip), tt);
}
Multimap newFreqEntries = HashMultimap.create();
for (FrequencyEntry fe : frequencyEntries) {
newFreqEntries.put(graph.index.patternForTrip.get(fe.tripTimes.trip), fe);
}
// filter to just the patterns that are relevant, then replace each pattern with a new pattern
// representing its modified trips
graphPatterns = graphPatterns.stream()
.filter(p -> newScheduledPatterns.containsKey(p) || newFreqEntries.containsKey(p))
.map(p -> {
TripPattern newp = new TripPattern(p.route, p.stopPattern);
newScheduledPatterns.get(p).stream().forEach(newp.scheduledTimetable::addTripTimes);
newFreqEntries.get(p).stream().forEach(newp.scheduledTimetable::addFrequencyEntry);
return newp;
})
.collect(Collectors.toList());
}
}
/* Make timetables for active trip patterns and record the stops each active pattern uses. */
for (TripPattern originalPattern : graphPatterns) {
Collection patterns = Arrays.asList(originalPattern);
// apply filters. note that a filter can create multiple trip patterns from a single trip pattern
// so we need to make sure we handle all of them
if (scenario != null && scenario.modifications != null) {
for (TripPatternFilter filter : Iterables
.filter(scenario.modifications, TripPatternFilter.class)) {
Collection modifiedPatterns = Lists.newArrayList();
for (TripPattern pattern : patterns) {
Collection result = filter.apply(pattern);
if (result != null)
modifiedPatterns.addAll(result);
}
// this is the result of this filter for all trip patterns
patterns = modifiedPatterns;
}
}
for (TripPattern pattern : patterns) {
RaptorWorkerTimetable timetable = RaptorWorkerTimetable
.forPattern(graph, pattern, window, scenario, ts);
if (timetable == null) {
// Pattern is not running during the time window
continue;
}
timetable.dataIndex = timetablesForPattern.size();
timetable.raptorData = this;
timetablesForPattern.add(timetable);
if (timetable.hasFrequencyTrips())
hasFrequencies = true;
if (timetable.hasScheduledTrips())
hasSchedules = true;
// Temporary bidirectional mapping between 0-based indexes and patterns
indexForPattern.put(pattern, patternForIndex.size());
patternForIndex.add(pattern);
patternNames.add(pattern.code);
TIntList stopIndexesForPattern = new TIntArrayList();
for (Stop stop : pattern.getStops()) {
int vidx = graph.index.stopVertexForStop.get(stop).getIndex();
int stopIndex = indexForStop.get(vidx);
if (stopIndex == -1) {
stopIndex = indexForStop.size();
indexForStop.put(vidx, stopIndex);
stopForIndex.add(vidx);
stopNames.add(stop.getName());
}
stopIndexesForPattern.add(stopIndex);
}
timetable.stopIndices = stopIndexesForPattern.toArray();
}
}
// and do roughly the same thing for added patterns
if (scenario != null && scenario.modifications != null) {
for (AddTripPattern atp : Iterables.filter(scenario.modifications, AddTripPattern.class)) {
// note that added trip patterns are not affected by modifications
RaptorWorkerTimetable timetable = RaptorWorkerTimetable.forAddedPattern(atp, window, ts);
if (timetable == null)
continue;
timetable.dataIndex = timetablesForPattern.size();
timetablesForPattern.add(timetable);
timetable.raptorData = this;
if (timetable.hasFrequencyTrips())
this.hasFrequencies = true;
if (timetable.hasScheduledTrips())
this.hasSchedules = true;
// TODO: patternForIndex, indexForPattern
patternNames.add(atp.name);
// create the stops for the pattern, and collect the temporary stops
for (AddTripPattern.TemporaryStop t : atp.temporaryStops) {
// the index of this stop in the worker data
int stopIndex = stopForIndex.size();
addedStops.put(t, stopIndex);
indexForStop.put(t.index, stopIndex);
stopForIndex.add(t.index);
}
timetable.stopIndices = Arrays.asList(atp.temporaryStops).stream()
.mapToInt(t -> indexForStop.get(t.index))
.toArray();
}
}
// for each of the added stops, compute transfers and a stop tree cache
// Indexed by vertex ID, not RAPTOR index
TIntObjectMap temporaryStopTreeCache = new TIntObjectHashMap<>();;
// Holds transfer both from _and_ to temporary stops
// Indexed by and contains vertex ID, not RAPTOR index
TIntObjectMap temporaryTransfers = new TIntObjectHashMap<>();
AStar astar = new AStar();
for (AddTripPattern.TemporaryStop t : addedStops.keySet()) {
// forward search: stop tree cache and transfers out
RoutingRequest rr = new RoutingRequest(TraverseMode.WALK);
rr.batch = true;
rr.from = rr.to = new GenericLocation(t.lat, t.lon);
try {
rr.setRoutingContext(graph);
} catch (VertexNotFoundException vnfe) {
LOG.warn("Temporary stop at {}, {} not connected to graph", t.lat, t.lon);
temporaryStopTreeCache.put(t.index, new int[0]);
temporaryTransfers.put(t.index, new TIntIntHashMap());
continue;
}
// We use walk-distance limiting and a least-walk dominance function in order to be consistent with egress walking
// which is implemented this way because walk times can change when walk speed changes. Also, walk times are floating
// point and can change slightly when streets are split. Street lengths are internally fixed-point ints, which do not
// suffer from roundoff. Great care is taken when splitting to preserve sums.
// When cycling, this is not an issue; we already have an explicitly asymmetrical search (cycling at the origin, walking at the destination),
// so we need not preserve symmetry.
rr.maxWalkDistance = 2000;
rr.softWalkLimiting = false;
rr.dominanceFunction = new DominanceFunction.LeastWalk();
rr.longDistance = true;
rr.numItineraries = 1;
ShortestPathTree spt = astar.getShortestPathTree(rr, 5);
// create the stop tree cache
// TODO duplicated code from stopTreeCache
// Copy vertex indices and distances into a flattened 2D array
int[] distances = new int[spt.getVertexCount() * 2];
int i = 0;
for (Vertex vertex : spt.getVertices()) {
State state = spt.getState(vertex);
if (state == null)
continue;
distances[i++] = vertex.getIndex();
distances[i++] = (int) state.getWalkDistance();
}
temporaryStopTreeCache.put(t.index, distances);
// NB using walk speed of 1 m/s here since we want meters, not seconds
// walk speed is applied during search.
TIntIntMap transfersFromStop = findStopsNear(spt, graph, false, 1f);
// convert it to use indices in the graph not in the worker data
TIntIntMap transfersFromStopWithGraphIndices = new TIntIntHashMap();
for (TIntIntIterator trIt = transfersFromStop.iterator(); trIt.hasNext();) {
trIt.advance();
transfersFromStopWithGraphIndices.put(stopForIndex.get(trIt.key()), trIt.value());
}
temporaryTransfers.put(t.index, transfersFromStopWithGraphIndices);
rr.cleanup();
// now compute transfers to the stop by doing a batch arrive-by search
// necessary to hand-clear routing context so that it is not cached
rr.rctx = null;
rr.setArriveBy(true);
// reset routing context because temporary edges face the wrong way
rr.setRoutingContext(graph);
spt = astar.getShortestPathTree(rr, 5);
// NB using walk speed of 1 m/s here since we want meters, not seconds
// walk speed is applied during search
TIntIntMap transfersToStop = findStopsNear(spt, graph, false, 1f);
// turn the array around; these are transfers from elsewhere to this stop.
for (TIntIntIterator it = transfersToStop.iterator(); it.hasNext(); ) {
it.advance();
// index of vertex in graph
int graphIndex = stopForIndex.get(it.key());
// for absolute determinism we want to ensure that transfers between two added stops are always computed
// in the forward direction. Otherwise they would be computed twice, once forwards
// and once reverse, and which one was saved would depend on iteration order.
// OTP should be symmetrical but let's not write code that depends on that property
Vertex tstop = graph.getVertexById(graphIndex);
if (tstop == null || !TransitStop.class.isInstance(tstop))
// this is not a permanent stop - there is no transit stop vertex associated with it
continue;
if (!temporaryTransfers.containsKey(graphIndex))
temporaryTransfers.put(graphIndex, new TIntIntHashMap());
// temporary transfers are stored by index in the graph not the worker data
temporaryTransfers.get(graphIndex).put(t.index, it.value());
}
}
// create the mapping from stops to patterns
TIntObjectMap patternsForStopList = new TIntObjectHashMap<>();
for (int pattern = 0; pattern < timetablesForPattern.size(); pattern++) {
for (int stop : timetablesForPattern.get(pattern).stopIndices) {
if (!patternsForStopList.containsKey(stop))
patternsForStopList.put(stop, new TIntArrayList());
patternsForStopList.get(stop).add(pattern);
}
}
for (int stop = 0; patternsForStopList.containsKey(stop); stop++) {
patternsForStop.add(patternsForStopList.get(stop).toArray());
}
/** Record transfers between all used stops. */
for (TIntIterator it = stopForIndex.iterator(); it.hasNext();) {
int stop = it.next();
TIntList transfers = new TIntArrayList();
TransitStop tstop = (TransitStop) graph.getVertexById(stop);
if (tstop != null) {
// not an added stop, look for transfers in the graph
for (SimpleTransfer simpleTransfer : Iterables
.filter(tstop.getOutgoing(), SimpleTransfer.class)) {
int targetStopIndex = indexForStop.get(simpleTransfer.getToVertex().getIndex());
if (targetStopIndex != -1) {
transfers.add(targetStopIndex);
transfers.add((int) (simpleTransfer.getDistance()));
}
}
}
// check for any transfers to/from added stops
if (temporaryTransfers.containsKey(stop)) {
for (TIntIntIterator tranIt = temporaryTransfers.get(stop).iterator(); tranIt.hasNext();) {
tranIt.advance();
// stop index
transfers.add(indexForStop.get(tranIt.key()));
// distance
transfers.add(tranIt.value());
}
}
if (!transfers.isEmpty())
transfersForStop.add(transfers.toArray());
else
transfersForStop.add(EMPTY_INT_ARRAY);
}
long stcStart = System.currentTimeMillis();
StopTreeCache stc = graph.index.getStopTreeCache();
ts.stopTreeCaching = (int) (System.currentTimeMillis() - stcStart);
// Record times to nearby intersections for all used stops.
// We use times rather than distances to avoid a costly floating-point divide during propagation
if (sampleSet == null) {
int maxWalkDistance = (int) (req.maxWalkTime * 60 * req.walkSpeed);
for (TIntIterator stopIt = stopForIndex.iterator(); stopIt.hasNext();) {
int stop = stopIt.next();
// permanent stop
Vertex tstop = graph.getVertexById(stop);
boolean isPermanentStop = tstop != null && TransitStop.class.isInstance(tstop);
// convert distance to time
int[] distancesForStop = isPermanentStop ? stc.distancesForStop.get(tstop) : temporaryStopTreeCache.get(stop);
TIntList timesForStop = new TIntArrayList();
for (int i = 0; i < distancesForStop.length; i += 2) {
int vidx = distancesForStop[i];
int dist = distancesForStop[i + 1];
// only add if it's less than the max walk distance
if (dist <= maxWalkDistance) {
timesForStop.add(vidx);
// convert meters to seconds by dividing by meters / second
timesForStop.add((int) (dist / req.walkSpeed));
}
}
targetsForStop.add(timesForStop.toArray());
}
// TODO memory leak when many graphs have been built
nTargets = Vertex.getMaxIndex();
}
// Record distances to each sample
// We need to propagate all the way to samples when doing repeated RAPTOR.
// Consider the situation where there are two parallel transit lines on
// 5th Street and 6th Street, and you live on A Street halfway between 5th and 6th.
// Both lines run at 30 minute headways, but they are exactly out of phase, and for the
// purposes of this conversation both go the same place with the same in-vehicle travel time.
// Thus, even though the lines run every 30 minutes, you never experience a wait of more than
// 15 minutes because you are clever when you choose which line to take. The worst case at each
// transit stop is much worse than the worst case at samples. While unlikely, it is possible that
// a sample would be able to reach these two stops within the walk limit, but that the two
// intersections it is connected to cannot reach both.
else {
TIntObjectMap> sampleIndex = new TIntObjectHashMap>();
for (int i = 0; i < sampleSet.pset.capacity; i++) {
if (sampleSet.v0s[i] == null)
continue;
// VERTEX 0
int v0 = sampleSet.v0s[i].getIndex();
List list;
if (sampleIndex.containsKey(v0))
list = sampleIndex.get(v0);
else {
list = new ArrayList();
sampleIndex.put(v0, list);
}
list.add(new HalfSample(i, sampleSet.d0s[i]));
// VERTEX 1
if (sampleSet.v1s[i] != null) {
int v1 = sampleSet.v1s[i].getIndex();
if (sampleIndex.containsKey(v1))
list = sampleIndex.get(v1);
else {
list = new ArrayList();
sampleIndex.put(v1, list);
}
list.add(new HalfSample(i, sampleSet.d1s[i]));
}
}
// Iterate over all stops, saving the least distance to each reachable sample from
// from each transit stop.
// We first make a map stops to samples, so we can ensure we save only the shortest
// distance from a transit stop to a sample. Most transit stops can reach a given sample two
// ways because they can reach both of the vertices the sample is connected to.
TIntIntMap out = new TIntIntHashMap();
for (TIntIterator stopIt = stopForIndex.iterator(); stopIt.hasNext();) {
out.clear();
int stop = stopIt.next();
int[] distancesForStop;
Vertex tstop = graph.getVertexById(stop);
if (tstop != null && TransitStop.class.isInstance(tstop))
// permanent stop
distancesForStop = stc.distancesForStop.get(tstop);
else
// temporary stop
distancesForStop = temporaryStopTreeCache.get(stop);
STREET: for (int i = 0; i < distancesForStop.length; i++) {
int v = distancesForStop[i++];
int d = distancesForStop[i];
if (!sampleIndex.containsKey(v))
continue STREET;
// Build the map
SAMPLE: for (HalfSample s : sampleIndex.get(v)) {
int distance = Math.round(d + s.distance);
if (distance > stc.maxWalkMeters)
continue;
// only save it if there isn't another shorter walking path that we've already encountered.
int time = (int) (distance / req.walkSpeed);
if (!out.containsKey(s.index) || out.get(s.index) > time)
out.put(s.index, time);
}
}
// Save a flat array of (target, distance) pairs keyed on this transit stops's index in the RAPTOR table.
int[] flat = new int[out.size() * 2];
int pos = 0;
for (TIntIntIterator it = out.iterator(); it.hasNext();) {
it.advance();
flat[pos++] = it.key();
flat[pos++] = it.value();
}
targetsForStop.add(flat);
}
nTargets = sampleSet.pset.capacity;
}
// store transfer rules by stop
if (scenario != null && scenario.modifications != null) {
for (TransferRule tr : Iterables.filter(scenario.modifications, TransferRule.class)) {
if (tr.stop == null) {
this.baseTransferRules.add(tr);
}
else {
Vertex tstop = graph.getVertex(tr.stop);
if (tstop == null || !TransitStop.class.isInstance(tstop))
LOG.warn("Transit stop not found for transfer rule with stop label {}", tr.stop);
if (!indexForStop.containsKey(tstop.getIndex()))
// this stop is not used in this time window
continue;
int index = indexForStop.get(tstop.getIndex());
if (!transferRules.containsKey(index))
transferRules.put(index, new ArrayList<>());
transferRules.get(index).add(tr);
}
}
}
ts.stopCount = nStops = stopForIndex.size();
ts.patternCount = nPatterns = timetablesForPattern.size();
ts.targetCount = nTargets;
}
/** find stops from a given SPT, including temporary stops. If useTimes is true, use times from the SPT, otherwise use distances */
public TIntIntMap findStopsNear (ShortestPathTree spt, Graph graph, boolean useTimes, float walkSpeed) {
TIntIntMap accessTimes = new TIntIntHashMap();
for (TransitStop tstop : graph.index.stopVertexForStop.values()) {
State s = spt.getState(tstop);
if (s != null) {
// note that we calculate the time based on the walk speed here rather than
// based on the time. this matches what we do in the stop tree cache.
int stopIndex = indexForStop.get(tstop.getIndex());
if (stopIndex != -1) {
if (useTimes)
accessTimes.put(stopIndex, (int) s.getElapsedTimeSeconds());
else
accessTimes.put(stopIndex, (int) (s.getWalkDistance() / walkSpeed));
}
}
}
// and handle the additional stops
for (TObjectIntIterator it = addedStops.iterator(); it.hasNext();) {
it.advance();
AddTripPattern.TemporaryStop tstop = it.key();
if (tstop.sample == null) {
continue;
}
double dist = Double.POSITIVE_INFINITY;
if (tstop.sample.v0 != null) {
State s0 = spt.getState(tstop.sample.v0);
if (s0 != null) {
dist = s0.getWalkDistance() + tstop.sample.d0;
}
}
if (tstop.sample.v1 != null) {
State s1 = spt.getState(tstop.sample.v1);
if (s1 != null) {
double d1 = s1.getWalkDistance() + tstop.sample.d1;
dist = Double.isInfinite(dist) ? d1 : Math.min(d1, dist);
}
}
if (Double.isInfinite(dist))
continue;
// NB using the index in the worker data not the index in the graph!
accessTimes.put(it.value(), (int) (dist / walkSpeed));
}
return accessTimes;
}
/** half a sample: the index in the sample set, and the distance to one of the vertices */
private static class HalfSample {
public HalfSample(int index, float distance) {
this.index = index;
this.distance = distance;
}
int index;
float distance;
}
}
