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// https://github.com/topojson/topojson-server Version 3.0.0. Copyright 2017 Mike Bostock.
(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
typeof define === 'function' && define.amd ? define(['exports'], factory) :
(factory((global.topojson = global.topojson || {})));
}(this, (function (exports) { 'use strict';
// Computes the bounding box of the specified hash of GeoJSON objects.
var bounds = function(objects) {
var x0 = Infinity,
y0 = Infinity,
x1 = -Infinity,
y1 = -Infinity;
function boundGeometry(geometry) {
if (geometry != null && boundGeometryType.hasOwnProperty(geometry.type)) boundGeometryType[geometry.type](geometry);
}
var boundGeometryType = {
GeometryCollection: function(o) { o.geometries.forEach(boundGeometry); },
Point: function(o) { boundPoint(o.coordinates); },
MultiPoint: function(o) { o.coordinates.forEach(boundPoint); },
LineString: function(o) { boundLine(o.arcs); },
MultiLineString: function(o) { o.arcs.forEach(boundLine); },
Polygon: function(o) { o.arcs.forEach(boundLine); },
MultiPolygon: function(o) { o.arcs.forEach(boundMultiLine); }
};
function boundPoint(coordinates) {
var x = coordinates[0],
y = coordinates[1];
if (x < x0) x0 = x;
if (x > x1) x1 = x;
if (y < y0) y0 = y;
if (y > y1) y1 = y;
}
function boundLine(coordinates) {
coordinates.forEach(boundPoint);
}
function boundMultiLine(coordinates) {
coordinates.forEach(boundLine);
}
for (var key in objects) {
boundGeometry(objects[key]);
}
return x1 >= x0 && y1 >= y0 ? [x0, y0, x1, y1] : undefined;
};
var hashset = function(size, hash, equal, type, empty) {
if (arguments.length === 3) {
type = Array;
empty = null;
}
var store = new type(size = 1 << Math.max(4, Math.ceil(Math.log(size) / Math.LN2))),
mask = size - 1;
for (var i = 0; i < size; ++i) {
store[i] = empty;
}
function add(value) {
var index = hash(value) & mask,
match = store[index],
collisions = 0;
while (match != empty) {
if (equal(match, value)) return true;
if (++collisions >= size) throw new Error("full hashset");
match = store[index = (index + 1) & mask];
}
store[index] = value;
return true;
}
function has(value) {
var index = hash(value) & mask,
match = store[index],
collisions = 0;
while (match != empty) {
if (equal(match, value)) return true;
if (++collisions >= size) break;
match = store[index = (index + 1) & mask];
}
return false;
}
function values() {
var values = [];
for (var i = 0, n = store.length; i < n; ++i) {
var match = store[i];
if (match != empty) values.push(match);
}
return values;
}
return {
add: add,
has: has,
values: values
};
};
var hashmap = function(size, hash, equal, keyType, keyEmpty, valueType) {
if (arguments.length === 3) {
keyType = valueType = Array;
keyEmpty = null;
}
var keystore = new keyType(size = 1 << Math.max(4, Math.ceil(Math.log(size) / Math.LN2))),
valstore = new valueType(size),
mask = size - 1;
for (var i = 0; i < size; ++i) {
keystore[i] = keyEmpty;
}
function set(key, value) {
var index = hash(key) & mask,
matchKey = keystore[index],
collisions = 0;
while (matchKey != keyEmpty) {
if (equal(matchKey, key)) return valstore[index] = value;
if (++collisions >= size) throw new Error("full hashmap");
matchKey = keystore[index = (index + 1) & mask];
}
keystore[index] = key;
valstore[index] = value;
return value;
}
function maybeSet(key, value) {
var index = hash(key) & mask,
matchKey = keystore[index],
collisions = 0;
while (matchKey != keyEmpty) {
if (equal(matchKey, key)) return valstore[index];
if (++collisions >= size) throw new Error("full hashmap");
matchKey = keystore[index = (index + 1) & mask];
}
keystore[index] = key;
valstore[index] = value;
return value;
}
function get(key, missingValue) {
var index = hash(key) & mask,
matchKey = keystore[index],
collisions = 0;
while (matchKey != keyEmpty) {
if (equal(matchKey, key)) return valstore[index];
if (++collisions >= size) break;
matchKey = keystore[index = (index + 1) & mask];
}
return missingValue;
}
function keys() {
var keys = [];
for (var i = 0, n = keystore.length; i < n; ++i) {
var matchKey = keystore[i];
if (matchKey != keyEmpty) keys.push(matchKey);
}
return keys;
}
return {
set: set,
maybeSet: maybeSet, // set if unset
get: get,
keys: keys
};
};
var equalPoint = function(pointA, pointB) {
return pointA[0] === pointB[0] && pointA[1] === pointB[1];
};
// TODO if quantized, use simpler Int32 hashing?
var buffer = new ArrayBuffer(16);
var floats = new Float64Array(buffer);
var uints = new Uint32Array(buffer);
var hashPoint = function(point) {
floats[0] = point[0];
floats[1] = point[1];
var hash = uints[0] ^ uints[1];
hash = hash << 5 ^ hash >> 7 ^ uints[2] ^ uints[3];
return hash & 0x7fffffff;
};
// Given an extracted (pre-)topology, identifies all of the junctions. These are
// the points at which arcs (lines or rings) will need to be cut so that each
// arc is represented uniquely.
//
// A junction is a point where at least one arc deviates from another arc going
// through the same point. For example, consider the point B. If there is a arc
// through ABC and another arc through CBA, then B is not a junction because in
// both cases the adjacent point pairs are {A,C}. However, if there is an
// additional arc ABD, then {A,D} != {A,C}, and thus B becomes a junction.
//
// For a closed ring ABCA, the first point A’s adjacent points are the second
// and last point {B,C}. For a line, the first and last point are always
// considered junctions, even if the line is closed; this ensures that a closed
// line is never rotated.
var join = function(topology) {
var coordinates = topology.coordinates,
lines = topology.lines,
rings = topology.rings,
indexes = index(),
visitedByIndex = new Int32Array(coordinates.length),
leftByIndex = new Int32Array(coordinates.length),
rightByIndex = new Int32Array(coordinates.length),
junctionByIndex = new Int8Array(coordinates.length),
junctionCount = 0, // upper bound on number of junctions
i, n,
previousIndex,
currentIndex,
nextIndex;
for (i = 0, n = coordinates.length; i < n; ++i) {
visitedByIndex[i] = leftByIndex[i] = rightByIndex[i] = -1;
}
for (i = 0, n = lines.length; i < n; ++i) {
var line = lines[i],
lineStart = line[0],
lineEnd = line[1];
currentIndex = indexes[lineStart];
nextIndex = indexes[++lineStart];
++junctionCount, junctionByIndex[currentIndex] = 1; // start
while (++lineStart <= lineEnd) {
sequence(i, previousIndex = currentIndex, currentIndex = nextIndex, nextIndex = indexes[lineStart]);
}
++junctionCount, junctionByIndex[nextIndex] = 1; // end
}
for (i = 0, n = coordinates.length; i < n; ++i) {
visitedByIndex[i] = -1;
}
for (i = 0, n = rings.length; i < n; ++i) {
var ring = rings[i],
ringStart = ring[0] + 1,
ringEnd = ring[1];
previousIndex = indexes[ringEnd - 1];
currentIndex = indexes[ringStart - 1];
nextIndex = indexes[ringStart];
sequence(i, previousIndex, currentIndex, nextIndex);
while (++ringStart <= ringEnd) {
sequence(i, previousIndex = currentIndex, currentIndex = nextIndex, nextIndex = indexes[ringStart]);
}
}
function sequence(i, previousIndex, currentIndex, nextIndex) {
if (visitedByIndex[currentIndex] === i) return; // ignore self-intersection
visitedByIndex[currentIndex] = i;
var leftIndex = leftByIndex[currentIndex];
if (leftIndex >= 0) {
var rightIndex = rightByIndex[currentIndex];
if ((leftIndex !== previousIndex || rightIndex !== nextIndex)
&& (leftIndex !== nextIndex || rightIndex !== previousIndex)) {
++junctionCount, junctionByIndex[currentIndex] = 1;
}
} else {
leftByIndex[currentIndex] = previousIndex;
rightByIndex[currentIndex] = nextIndex;
}
}
function index() {
var indexByPoint = hashmap(coordinates.length * 1.4, hashIndex, equalIndex, Int32Array, -1, Int32Array),
indexes = new Int32Array(coordinates.length);
for (var i = 0, n = coordinates.length; i < n; ++i) {
indexes[i] = indexByPoint.maybeSet(i, i);
}
return indexes;
}
function hashIndex(i) {
return hashPoint(coordinates[i]);
}
function equalIndex(i, j) {
return equalPoint(coordinates[i], coordinates[j]);
}
visitedByIndex = leftByIndex = rightByIndex = null;
var junctionByPoint = hashset(junctionCount * 1.4, hashPoint, equalPoint), j;
// Convert back to a standard hashset by point for caller convenience.
for (i = 0, n = coordinates.length; i < n; ++i) {
if (junctionByIndex[j = indexes[i]]) {
junctionByPoint.add(coordinates[j]);
}
}
return junctionByPoint;
};
// Given an extracted (pre-)topology, cuts (or rotates) arcs so that all shared
// point sequences are identified. The topology can then be subsequently deduped
// to remove exact duplicate arcs.
var cut = function(topology) {
var junctions = join(topology),
coordinates = topology.coordinates,
lines = topology.lines,
rings = topology.rings,
next,
i, n;
for (i = 0, n = lines.length; i < n; ++i) {
var line = lines[i],
lineMid = line[0],
lineEnd = line[1];
while (++lineMid < lineEnd) {
if (junctions.has(coordinates[lineMid])) {
next = {0: lineMid, 1: line[1]};
line[1] = lineMid;
line = line.next = next;
}
}
}
for (i = 0, n = rings.length; i < n; ++i) {
var ring = rings[i],
ringStart = ring[0],
ringMid = ringStart,
ringEnd = ring[1],
ringFixed = junctions.has(coordinates[ringStart]);
while (++ringMid < ringEnd) {
if (junctions.has(coordinates[ringMid])) {
if (ringFixed) {
next = {0: ringMid, 1: ring[1]};
ring[1] = ringMid;
ring = ring.next = next;
} else { // For the first junction, we can rotate rather than cut.
rotateArray(coordinates, ringStart, ringEnd, ringEnd - ringMid);
coordinates[ringEnd] = coordinates[ringStart];
ringFixed = true;
ringMid = ringStart; // restart; we may have skipped junctions
}
}
}
}
return topology;
};
function rotateArray(array, start, end, offset) {
reverse(array, start, end);
reverse(array, start, start + offset);
reverse(array, start + offset, end);
}
function reverse(array, start, end) {
for (var mid = start + ((end-- - start) >> 1), t; start < mid; ++start, --end) {
t = array[start], array[start] = array[end], array[end] = t;
}
}
// Given a cut topology, combines duplicate arcs.
var dedup = function(topology) {
var coordinates = topology.coordinates,
lines = topology.lines, line,
rings = topology.rings, ring,
arcCount = lines.length + rings.length,
i, n;
delete topology.lines;
delete topology.rings;
// Count the number of (non-unique) arcs to initialize the hashmap safely.
for (i = 0, n = lines.length; i < n; ++i) {
line = lines[i]; while (line = line.next) ++arcCount;
}
for (i = 0, n = rings.length; i < n; ++i) {
ring = rings[i]; while (ring = ring.next) ++arcCount;
}
var arcsByEnd = hashmap(arcCount * 2 * 1.4, hashPoint, equalPoint),
arcs = topology.arcs = [];
for (i = 0, n = lines.length; i < n; ++i) {
line = lines[i];
do {
dedupLine(line);
} while (line = line.next);
}
for (i = 0, n = rings.length; i < n; ++i) {
ring = rings[i];
if (ring.next) { // arc is no longer closed
do {
dedupLine(ring);
} while (ring = ring.next);
} else {
dedupRing(ring);
}
}
function dedupLine(arc) {
var startPoint,
endPoint,
startArcs, startArc,
endArcs, endArc,
i, n;
// Does this arc match an existing arc in order?
if (startArcs = arcsByEnd.get(startPoint = coordinates[arc[0]])) {
for (i = 0, n = startArcs.length; i < n; ++i) {
startArc = startArcs[i];
if (equalLine(startArc, arc)) {
arc[0] = startArc[0];
arc[1] = startArc[1];
return;
}
}
}
// Does this arc match an existing arc in reverse order?
if (endArcs = arcsByEnd.get(endPoint = coordinates[arc[1]])) {
for (i = 0, n = endArcs.length; i < n; ++i) {
endArc = endArcs[i];
if (reverseEqualLine(endArc, arc)) {
arc[1] = endArc[0];
arc[0] = endArc[1];
return;
}
}
}
if (startArcs) startArcs.push(arc); else arcsByEnd.set(startPoint, [arc]);
if (endArcs) endArcs.push(arc); else arcsByEnd.set(endPoint, [arc]);
arcs.push(arc);
}
function dedupRing(arc) {
var endPoint,
endArcs,
endArc,
i, n;
// Does this arc match an existing line in order, or reverse order?
// Rings are closed, so their start point and end point is the same.
if (endArcs = arcsByEnd.get(endPoint = coordinates[arc[0]])) {
for (i = 0, n = endArcs.length; i < n; ++i) {
endArc = endArcs[i];
if (equalRing(endArc, arc)) {
arc[0] = endArc[0];
arc[1] = endArc[1];
return;
}
if (reverseEqualRing(endArc, arc)) {
arc[0] = endArc[1];
arc[1] = endArc[0];
return;
}
}
}
// Otherwise, does this arc match an existing ring in order, or reverse order?
if (endArcs = arcsByEnd.get(endPoint = coordinates[arc[0] + findMinimumOffset(arc)])) {
for (i = 0, n = endArcs.length; i < n; ++i) {
endArc = endArcs[i];
if (equalRing(endArc, arc)) {
arc[0] = endArc[0];
arc[1] = endArc[1];
return;
}
if (reverseEqualRing(endArc, arc)) {
arc[0] = endArc[1];
arc[1] = endArc[0];
return;
}
}
}
if (endArcs) endArcs.push(arc); else arcsByEnd.set(endPoint, [arc]);
arcs.push(arc);
}
function equalLine(arcA, arcB) {
var ia = arcA[0], ib = arcB[0],
ja = arcA[1], jb = arcB[1];
if (ia - ja !== ib - jb) return false;
for (; ia <= ja; ++ia, ++ib) if (!equalPoint(coordinates[ia], coordinates[ib])) return false;
return true;
}
function reverseEqualLine(arcA, arcB) {
var ia = arcA[0], ib = arcB[0],
ja = arcA[1], jb = arcB[1];
if (ia - ja !== ib - jb) return false;
for (; ia <= ja; ++ia, --jb) if (!equalPoint(coordinates[ia], coordinates[jb])) return false;
return true;
}
function equalRing(arcA, arcB) {
var ia = arcA[0], ib = arcB[0],
ja = arcA[1], jb = arcB[1],
n = ja - ia;
if (n !== jb - ib) return false;
var ka = findMinimumOffset(arcA),
kb = findMinimumOffset(arcB);
for (var i = 0; i < n; ++i) {
if (!equalPoint(coordinates[ia + (i + ka) % n], coordinates[ib + (i + kb) % n])) return false;
}
return true;
}
function reverseEqualRing(arcA, arcB) {
var ia = arcA[0], ib = arcB[0],
ja = arcA[1], jb = arcB[1],
n = ja - ia;
if (n !== jb - ib) return false;
var ka = findMinimumOffset(arcA),
kb = n - findMinimumOffset(arcB);
for (var i = 0; i < n; ++i) {
if (!equalPoint(coordinates[ia + (i + ka) % n], coordinates[jb - (i + kb) % n])) return false;
}
return true;
}
// Rings are rotated to a consistent, but arbitrary, start point.
// This is necessary to detect when a ring and a rotated copy are dupes.
function findMinimumOffset(arc) {
var start = arc[0],
end = arc[1],
mid = start,
minimum = mid,
minimumPoint = coordinates[mid];
while (++mid < end) {
var point = coordinates[mid];
if (point[0] < minimumPoint[0] || point[0] === minimumPoint[0] && point[1] < minimumPoint[1]) {
minimum = mid;
minimumPoint = point;
}
}
return minimum - start;
}
return topology;
};
// Given an array of arcs in absolute (but already quantized!) coordinates,
// converts to fixed-point delta encoding.
// This is a destructive operation that modifies the given arcs!
var delta = function(arcs) {
var i = -1,
n = arcs.length;
while (++i < n) {
var arc = arcs[i],
j = 0,
k = 1,
m = arc.length,
point = arc[0],
x0 = point[0],
y0 = point[1],
x1,
y1;
while (++j < m) {
point = arc[j], x1 = point[0], y1 = point[1];
if (x1 !== x0 || y1 !== y0) arc[k++] = [x1 - x0, y1 - y0], x0 = x1, y0 = y1;
}
if (k === 1) arc[k++] = [0, 0]; // Each arc must be an array of two or more positions.
arc.length = k;
}
return arcs;
};
// Extracts the lines and rings from the specified hash of geometry objects.
//
// Returns an object with three properties:
//
// * coordinates - shared buffer of [x, y] coordinates
// * lines - lines extracted from the hash, of the form [start, end]
// * rings - rings extracted from the hash, of the form [start, end]
//
// For each ring or line, start and end represent inclusive indexes into the
// coordinates buffer. For rings (and closed lines), coordinates[start] equals
// coordinates[end].
//
// For each line or polygon geometry in the input hash, including nested
// geometries as in geometry collections, the `coordinates` array is replaced
// with an equivalent `arcs` array that, for each line (for line string
// geometries) or ring (for polygon geometries), points to one of the above
// lines or rings.
var extract = function(objects) {
var index = -1,
lines = [],
rings = [],
coordinates = [];
function extractGeometry(geometry) {
if (geometry && extractGeometryType.hasOwnProperty(geometry.type)) extractGeometryType[geometry.type](geometry);
}
var extractGeometryType = {
GeometryCollection: function(o) { o.geometries.forEach(extractGeometry); },
LineString: function(o) { o.arcs = extractLine(o.arcs); },
MultiLineString: function(o) { o.arcs = o.arcs.map(extractLine); },
Polygon: function(o) { o.arcs = o.arcs.map(extractRing); },
MultiPolygon: function(o) { o.arcs = o.arcs.map(extractMultiRing); }
};
function extractLine(line) {
for (var i = 0, n = line.length; i < n; ++i) coordinates[++index] = line[i];
var arc = {0: index - n + 1, 1: index};
lines.push(arc);
return arc;
}
function extractRing(ring) {
for (var i = 0, n = ring.length; i < n; ++i) coordinates[++index] = ring[i];
var arc = {0: index - n + 1, 1: index};
rings.push(arc);
return arc;
}
function extractMultiRing(rings) {
return rings.map(extractRing);
}
for (var key in objects) {
extractGeometry(objects[key]);
}
return {
type: "Topology",
coordinates: coordinates,
lines: lines,
rings: rings,
objects: objects
};
};
// Given a hash of GeoJSON objects, returns a hash of GeoJSON geometry objects.
// Any null input geometry objects are represented as {type: null} in the output.
// Any feature.{id,properties,bbox} are transferred to the output geometry object.
// Each output geometry object is a shallow copy of the input (e.g., properties, coordinates)!
var geometry = function(inputs) {
var outputs = {}, key;
for (key in inputs) outputs[key] = geomifyObject(inputs[key]);
return outputs;
};
function geomifyObject(input) {
return input == null ? {type: null}
: (input.type === "FeatureCollection" ? geomifyFeatureCollection
: input.type === "Feature" ? geomifyFeature
: geomifyGeometry)(input);
}
function geomifyFeatureCollection(input) {
var output = {type: "GeometryCollection", geometries: input.features.map(geomifyFeature)};
if (input.bbox != null) output.bbox = input.bbox;
return output;
}
function geomifyFeature(input) {
var output = geomifyGeometry(input.geometry), key; // eslint-disable-line no-unused-vars
if (input.id != null) output.id = input.id;
if (input.bbox != null) output.bbox = input.bbox;
for (key in input.properties) { output.properties = input.properties; break; }
return output;
}
function geomifyGeometry(input) {
if (input == null) return {type: null};
var output = input.type === "GeometryCollection" ? {type: "GeometryCollection", geometries: input.geometries.map(geomifyGeometry)}
: input.type === "Point" || input.type === "MultiPoint" ? {type: input.type, coordinates: input.coordinates}
: {type: input.type, arcs: input.coordinates}; // TODO Check for unknown types?
if (input.bbox != null) output.bbox = input.bbox;
return output;
}
var prequantize = function(objects, bbox, n) {
var x0 = bbox[0],
y0 = bbox[1],
x1 = bbox[2],
y1 = bbox[3],
kx = x1 - x0 ? (n - 1) / (x1 - x0) : 1,
ky = y1 - y0 ? (n - 1) / (y1 - y0) : 1;
function quantizePoint(input) {
return [Math.round((input[0] - x0) * kx), Math.round((input[1] - y0) * ky)];
}
function quantizePoints(input, m) {
var i = -1,
j = 0,
n = input.length,
output = new Array(n), // pessimistic
pi,
px,
py,
x,
y;
while (++i < n) {
pi = input[i];
x = Math.round((pi[0] - x0) * kx);
y = Math.round((pi[1] - y0) * ky);
if (x !== px || y !== py) output[j++] = [px = x, py = y]; // non-coincident points
}
output.length = j;
while (j < m) j = output.push([output[0][0], output[0][1]]);
return output;
}
function quantizeLine(input) {
return quantizePoints(input, 2);
}
function quantizeRing(input) {
return quantizePoints(input, 4);
}
function quantizePolygon(input) {
return input.map(quantizeRing);
}
function quantizeGeometry(o) {
if (o != null && quantizeGeometryType.hasOwnProperty(o.type)) quantizeGeometryType[o.type](o);
}
var quantizeGeometryType = {
GeometryCollection: function(o) { o.geometries.forEach(quantizeGeometry); },
Point: function(o) { o.coordinates = quantizePoint(o.coordinates); },
MultiPoint: function(o) { o.coordinates = o.coordinates.map(quantizePoint); },
LineString: function(o) { o.arcs = quantizeLine(o.arcs); },
MultiLineString: function(o) { o.arcs = o.arcs.map(quantizeLine); },
Polygon: function(o) { o.arcs = quantizePolygon(o.arcs); },
MultiPolygon: function(o) { o.arcs = o.arcs.map(quantizePolygon); }
};
for (var key in objects) {
quantizeGeometry(objects[key]);
}
return {
scale: [1 / kx, 1 / ky],
translate: [x0, y0]
};
};
// Constructs the TopoJSON Topology for the specified hash of features.
// Each object in the specified hash must be a GeoJSON object,
// meaning FeatureCollection, a Feature or a geometry object.
var topology = function(objects, quantization) {
var bbox = bounds(objects = geometry(objects)),
transform = quantization > 0 && bbox && prequantize(objects, bbox, quantization),
topology = dedup(cut(extract(objects))),
coordinates = topology.coordinates,
indexByArc = hashmap(topology.arcs.length * 1.4, hashArc, equalArc);
objects = topology.objects; // for garbage collection
topology.bbox = bbox;
topology.arcs = topology.arcs.map(function(arc, i) {
indexByArc.set(arc, i);
return coordinates.slice(arc[0], arc[1] + 1);
});
delete topology.coordinates;
coordinates = null;
function indexGeometry(geometry$$1) {
if (geometry$$1 && indexGeometryType.hasOwnProperty(geometry$$1.type)) indexGeometryType[geometry$$1.type](geometry$$1);
}
var indexGeometryType = {
GeometryCollection: function(o) { o.geometries.forEach(indexGeometry); },
LineString: function(o) { o.arcs = indexArcs(o.arcs); },
MultiLineString: function(o) { o.arcs = o.arcs.map(indexArcs); },
Polygon: function(o) { o.arcs = o.arcs.map(indexArcs); },
MultiPolygon: function(o) { o.arcs = o.arcs.map(indexMultiArcs); }
};
function indexArcs(arc) {
var indexes = [];
do {
var index = indexByArc.get(arc);
indexes.push(arc[0] < arc[1] ? index : ~index);
} while (arc = arc.next);
return indexes;
}
function indexMultiArcs(arcs) {
return arcs.map(indexArcs);
}
for (var key in objects) {
indexGeometry(objects[key]);
}
if (transform) {
topology.transform = transform;
topology.arcs = delta(topology.arcs);
}
return topology;
};
function hashArc(arc) {
var i = arc[0], j = arc[1], t;
if (j < i) t = i, i = j, j = t;
return i + 31 * j;
}
function equalArc(arcA, arcB) {
var ia = arcA[0], ja = arcA[1],
ib = arcB[0], jb = arcB[1], t;
if (ja < ia) t = ia, ia = ja, ja = t;
if (jb < ib) t = ib, ib = jb, jb = t;
return ia === ib && ja === jb;
}
exports.topology = topology;
Object.defineProperty(exports, '__esModule', { value: true });
})));