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sasersaser
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java/2016/22: add solution for part 2
1 parent f850919 commit 7e437f1

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6 files changed

+103
-19
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6 files changed

+103
-19
lines changed

‎java/src/main/java/com/github/saser/adventofcode/year2016/day22/BUILD.bazel

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@@ -5,6 +5,7 @@ java_library(
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srcs = glob(["*.java"]),
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deps = [
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"//java/src/main/java/com/github/saser/adventofcode/geo:geo",
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"//java/src/main/java/com/github/saser/adventofcode/tuple:tuple",
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"//java/src/main/java/com/github/saser/adventofcode:adventofcode",
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],
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)

‎java/src/main/java/com/github/saser/adventofcode/year2016/day22/Day22.java

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@@ -3,13 +3,17 @@
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import java.io.BufferedReader;
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import java.io.Reader;
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import java.util.HashMap;
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import java.util.HashSet;
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import java.util.LinkedList;
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import java.util.Map;
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import java.util.Set;
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import java.util.regex.Pattern;
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import java.util.stream.Collectors;
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import com.github.saser.adventofcode.Result;
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import com.github.saser.adventofcode.geo.Point2D;
15+
import com.github.saser.adventofcode.tuple.Tuple2;
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import com.github.saser.adventofcode.tuple.Tuple3;
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public final class Day22 {
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public static Result part1(Reader r) {
@@ -22,8 +26,20 @@ public static Result part2(Reader r) {
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2327
private static Result solve(Reader r, int part) {
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var grid = Grid.parse(r);
25-
var count = grid.findViable().size();
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return Result.ok(Integer.toString(count));
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if (part == 1) {
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var count = grid.findViable().size();
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return Result.ok(Integer.toString(count));
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}
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var maxX = grid.nodes
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.keySet()
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.stream()
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.mapToInt(point -> point.x)
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.max()
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.getAsInt();
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var from = new Point2D(maxX, 0);
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var to = new Point2D(0, 0);
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var steps = grid.moveData(from, to);
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return Result.ok(Integer.toString(steps));
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}
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private static class Node {
@@ -97,5 +113,53 @@ public Set<Point2D> findViable() {
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.map(Map.Entry::getKey)
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.collect(Collectors.toSet());
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}
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public int moveData(Point2D from, Point2D to) {
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var queue = new LinkedList<Tuple3<Point2D, Point2D, Integer>>();
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var empty = this.findEmpty();
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queue.add(new Tuple3<>(empty, from.clone(), 0));
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var visited = new HashSet<Tuple2<Point2D, Point2D>>();
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var maxX = 0;
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var maxY = 0;
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for (var point : this.nodes.keySet()) {
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maxX = Math.max(maxX, point.x);
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maxY = Math.max(maxY, point.y);
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}
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var viable = this.findViable();
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viable.add(empty);
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while (!queue.isEmpty()) {
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var tuple = queue.remove();
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var emptyPosition = tuple.v1;
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var dataPosition = tuple.v2;
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var state = new Tuple2<>(emptyPosition, dataPosition);
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if (visited.contains(state)) {
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continue;
137+
}
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visited.add(state);
139+
var steps = tuple.v3;
140+
if (dataPosition.equals(to)) {
141+
return steps;
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}
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var neighbors = new Point2D[] {
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emptyPosition.plus(new Point2D(1, 0)),
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emptyPosition.plus(new Point2D(-1, 0)),
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emptyPosition.plus(new Point2D(0, 1)),
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emptyPosition.plus(new Point2D(0, -1)),
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};
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for (var neighbor : neighbors) {
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var nx = neighbor.x;
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var ny = neighbor.y;
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if (nx < 0 || nx > maxX || ny < 0 || ny > maxY) {
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continue;
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}
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if (!viable.contains(neighbor)) {
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continue;
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}
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var newDataPosition = (neighbor.equals(dataPosition) ? emptyPosition : dataPosition).clone();
159+
queue.add(new Tuple3<>(neighbor, newDataPosition, steps + 1));
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}
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}
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return -1;
163+
}
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}
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}

‎java/src/test/java/com/github/saser/adventofcode/year2016/day22/BUILD.bazel

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@@ -2,6 +2,7 @@ java_test(
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name = "test",
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srcs = glob(["*.java"]),
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test_class = "com.github.saser.adventofcode.year2016.day22.Day22Test",
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resources = ["//java/src/test/resources/com/github/saser/adventofcode/year2016/day22:testdata"],
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deps = [
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"@maven//:junit_junit",
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"//java/src/main/java/com/github/saser/adventofcode:adventofcode",

‎java/src/test/java/com/github/saser/adventofcode/year2016/day22/Day22Test.java

Lines changed: 18 additions & 17 deletions
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@@ -2,6 +2,7 @@
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import java.io.FileReader;
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import java.io.IOException;
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import java.io.InputStreamReader;
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import org.junit.Test;
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import org.junit.Assert;
@@ -17,22 +18,22 @@ public void part1Actual() throws IOException {
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}
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}
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20-
// @Test
21-
// public void part2Example() {
22-
// var input = new StringReader("");
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// var output = "";
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// var result = Day22.part2(input);
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// Assert.assertEquals("no error", "", result.error);
26-
// Assert.assertEquals("correct output", output, result.answer);
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// }
21+
@Test
22+
public void part2Example() {
23+
var input = new InputStreamReader(this.getClass().getResourceAsStream("example"));
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var output = "7";
25+
var result = Day22.part2(input);
26+
Assert.assertEquals("no error", "", result.error);
27+
Assert.assertEquals("correct output", output, result.answer);
28+
}
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29-
// @Test
30-
// public void part2Actual() throws IOException {
31-
// try (var input = new FileReader("inputs/2016/22")) {
32-
// var output = "";
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// var result = Day22.part2(input);
34-
// Assert.assertEquals("no error", "", result.error);
35-
// Assert.assertEquals("correct output", output, result.answer);
36-
// }
37-
// }
30+
@Test
31+
public void part2Actual() throws IOException {
32+
try (var input = new FileReader("inputs/2016/22")) {
33+
var output = "236";
34+
var result = Day22.part2(input);
35+
Assert.assertEquals("no error", "", result.error);
36+
Assert.assertEquals("correct output", output, result.answer);
37+
}
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}
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}

‎java/src/test/resources/com/github/saser/adventofcode/year2016/day22/BUILD.bazel

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package(default_visibility = ["//visibility:public"])
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filegroup(
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name = "testdata",
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testonly = 1,
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srcs = glob(["*"]),
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)

‎java/src/test/resources/com/github/saser/adventofcode/year2016/day22/example

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Filesystem Size Used Avail Use%
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/dev/grid/node-x0-y0 10T 8T 2T 80%
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/dev/grid/node-x0-y1 11T 6T 5T 54%
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/dev/grid/node-x0-y2 32T 28T 4T 87%
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/dev/grid/node-x1-y0 9T 7T 2T 77%
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/dev/grid/node-x1-y1 8T 0T 8T 0%
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/dev/grid/node-x1-y2 11T 7T 4T 63%
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/dev/grid/node-x2-y0 10T 6T 4T 60%
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/dev/grid/node-x2-y1 9T 8T 1T 88%
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/dev/grid/node-x2-y2 9T 6T 3T 66%

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