結果
| 問題 |
No.160 最短経路のうち辞書順最小
|
| コンテスト | |
| ユーザー |
 mikit
|
| 提出日時 | 2020-10-24 15:05:07 |
| 言語 | Java (openjdk 23) |
| 結果 |
AC
|
| 実行時間 | 135 ms / 5,000 ms |
| コード長 | 9,319 bytes |
| コンパイル時間 | 3,114 ms |
| コンパイル使用メモリ | 85,612 KB |
| 実行使用メモリ | 40,944 KB |
| 最終ジャッジ日時 | 2024-07-21 15:15:35 |
| 合計ジャッジ時間 | 6,953 ms |
|
ジャッジサーバーID （参考情報） |
judge5 / judge2 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 4 |
| other | AC * 26 |
ソースコード
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;
import java.nio.CharBuffer;
import java.util.PriorityQueue;
import java.io.IOException;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.StandardCharsets;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.io.UncheckedIOException;
import java.util.List;
import java.util.AbstractCollection;
import java.nio.charset.Charset;
import java.io.Writer;
import java.util.Comparator;
import java.util.NoSuchElementException;
import java.io.InputStream;
/**
* Built using CHelper reloaded plug-in
* Actual solution is at the top
*
* @author mikit
*/
public class Main {
public static void main(String[] args) {
InputStream inputStream = System.in;
OutputStream outputStream = System.out;
LightScanner2 in = new LightScanner2(inputStream);
LightWriter2 out = new LightWriter2(outputStream);
TaskD solver = new TaskD();
solver.solve(1, in, out);
out.close();
}
static class TaskD {
public void solve(int testNumber, LightScanner2 in, LightWriter2 out) {
int n = in.ints(), m = in.ints(), st = in.ints(), gl = in.ints();
List<List<TaskD.Edge>> g = new ArrayList<>(n);
for (int i = 0; i < n; i++) g.add(new ArrayList<>());
for (int i = 0; i < m; i++) {
int a = in.ints(), b = in.ints();
long c = in.longs();
g.get(b).add(new TaskD.Edge(a, c));
g.get(a).add(new TaskD.Edge(b, c));
}
long[] dist = new long[n];
int[] from = new int[n];
Arrays.fill(dist, 1L << 61);
Arrays.fill(from, -1);
dist[gl] = 0;
PriorityQueue<Integer> q = new PriorityQueue<>(Comparator.comparing(i -> dist[i]));
q.offer(gl);
while (!q.isEmpty()) {
int x = q.poll();
for (TaskD.Edge e : g.get(x)) {
long c = dist[x] + e.cost;
if (c < dist[e.to]) {
dist[e.to] = c;
from[e.to] = x;
q.offer(e.to);
} else if (c == dist[e.to]) {
from[e.to] = Math.min(from[e.to], x);
}
}
}
if (dist[st] >= (1L << 61)) {
out.ans(-1).ln();
return;
}
int now = st;
out.ans(st);
for (int i = 0; now != gl; i++) {
now = from[now];
out.ans(now);
}
out.ln();
}
private static class Edge {
int to;
long cost;
Edge(int to, long cost) {
this.to = to;
this.cost = cost;
}
}
}
static abstract class LightScannerAdapter implements AutoCloseable {
public abstract void close();
}
static class LightWriter2 implements AutoCloseable {
private static final int BUF_SIZE = 16 * 1024;
private final OutputStream out;
private final byte[] buf = new byte[BUF_SIZE];
private int ptr;
private boolean autoflush = false;
private boolean breaked = true;
public LightWriter2(OutputStream out) {
this.out = out;
}
public LightWriter2(Writer out) {
this.out = new LightWriter2.WriterOutputStream(out);
}
private void allocate(int n) {
if (ptr + n <= BUF_SIZE) return;
try {
out.write(buf, 0, ptr);
ptr = 0;
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
if (BUF_SIZE < n) throw new IllegalArgumentException("Internal buffer exceeded");
}
public void close() {
try {
out.write(buf, 0, ptr);
ptr = 0;
out.flush();
out.close();
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
}
private static int countDigits(int l) {
if (l >= 1000000000L) return 10;
if (l >= 100000000L) return 9;
if (l >= 10000000L) return 8;
if (l >= 1000000L) return 7;
if (l >= 100000L) return 6;
if (l >= 10000L) return 5;
if (l >= 1000L) return 4;
if (l >= 100L) return 3;
if (l >= 10L) return 2;
return 1;
}
public LightWriter2 ans(int x) {
allocate(12);
if (!breaked) buf[ptr++] = ' ';
breaked = false;
if (x < 0) {
buf[ptr++] = '-';
x = -x;
}
int n = countDigits(x);
for (int i = ptr + n - 1; ptr <= i; i--) {
buf[i] = (byte) (x % 10 + '0');
x /= 10;
}
ptr += n;
return this;
}
public LightWriter2 ln() {
allocate(1);
buf[ptr++] = '\n';
breaked = true;
if (autoflush) {
try {
out.flush();
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
}
return this;
}
private static class WriterOutputStream extends OutputStream {
final Writer writer;
final CharsetDecoder decoder;
WriterOutputStream(Writer writer) {
this.writer = writer;
this.decoder = StandardCharsets.UTF_8.newDecoder();
}
public void write(int b) throws IOException {
writer.write(b);
}
public void write(byte[] b) throws IOException {
writer.write(decoder.decode(ByteBuffer.wrap(b)).array());
}
public void write(byte[] b, int off, int len) throws IOException {
writer.write(decoder.decode(ByteBuffer.wrap(b, off, len)).array());
}
public void flush() throws IOException {
writer.flush();
}
public void close() throws IOException {
writer.close();
}
}
}
static class LightScanner2 extends LightScannerAdapter {
private static final int BUF_SIZE = 16 * 1024;
private final InputStream stream;
private final byte[] buf = new byte[BUF_SIZE];
private int ptr;
private int len;
public LightScanner2(InputStream stream) {
this.stream = stream;
}
private void reload() {
try {
ptr = 0;
len = stream.read(buf);
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
}
private void load(int n) {
if (ptr + n <= len) return;
System.arraycopy(buf, ptr, buf, 0, len - ptr);
len -= ptr;
ptr = 0;
try {
int r = stream.read(buf, len, BUF_SIZE - len);
if (r == -1) return;
len += r;
if (len != BUF_SIZE) buf[len] = '\n';
} catch (IOException ex) {
throw new UncheckedIOException(ex);
}
}
private void skip() {
while (len != -1) {
while (ptr < len && isTokenSeparator(buf[ptr])) ptr++;
if (ptr < len) return;
reload();
}
throw new NoSuchElementException("EOF");
}
public int ints() {
skip();
load(12);
int b = buf[ptr++];
boolean negate;
if (b == '-') {
negate = true;
b = buf[ptr++];
} else negate = false;
int x = 0;
for (; !isTokenSeparator(b); b = buf[ptr++]) {
if ('0' <= b && b <= '9') x = x * 10 + b - '0';
else throw new NumberFormatException("Unexpected character '" + ((char) b) + "'");
}
return negate ? -x : x;
}
public long longs() {
skip();
load(20);
int b = buf[ptr++];
boolean negate;
if (b == '-') {
negate = true;
b = buf[ptr++];
} else negate = false;
long x = 0;
for (; !isTokenSeparator(b); b = buf[ptr++]) {
if ('0' <= b && b <= '9') x = x * 10 + b - '0';
else throw new NumberFormatException("Unexpected character '" + b + "'");
}
return negate ? -x : x;
}
public void close() {
try {
stream.close();
} catch (IOException e) {
throw new UncheckedIOException(e);
}
}
private static boolean isTokenSeparator(int b) {
return b < 33 || 126 < b;
}
}
}