結果
問題 | No.1023 Cyclic Tour |
ユーザー |
|
提出日時 | 2020-04-14 01:35:49 |
言語 | Java (openjdk 23) |
結果 |
AC
|
実行時間 | 477 ms / 2,000 ms |
コード長 | 4,378 bytes |
コンパイル時間 | 2,719 ms |
コンパイル使用メモリ | 79,920 KB |
実行使用メモリ | 102,912 KB |
最終ジャッジ日時 | 2024-10-01 07:43:40 |
合計ジャッジ時間 | 23,217 ms |
ジャッジサーバーID (参考情報) |
judge2 / judge3 |
(要ログイン)
ファイルパターン | 結果 |
---|---|
sample | AC * 4 |
other | AC * 49 |
ソースコード
import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;import java.util.ArrayList;import java.util.Arrays;import java.util.NoSuchElementException;class DJSet {int n;int[] upper;public DJSet(int n) {this.n=n;upper=new int[n];Arrays.fill(upper, -1);}int root(int x) {return upper[x]<0?x:(upper[x]=root(upper[x]));}boolean equiv(int x,int y) {return root(x)==root(y);}void setUnion(int x,int y) {x=root(x);y=root(y);if(x==y) return;if (upper[x]<upper[y]) {x^=y;y^=x;x^=y;}if (upper[x]==upper[y]) --upper[y];upper[x]=y;}}public class Main {void dfs_uni(int cur,int par,ArrayList<Integer>[] g,int[] col) {col[cur]=1;for (int dst:g[cur]) {if (col[dst]==1) {System.out.println("Yes");System.exit(0);}if (col[dst]==0) dfs_uni(dst,cur,g,col);}col[cur]=2;}void dfs_bi(int cur,int par,ArrayList<Integer>[] g,int[] col) {col[cur]=1;for (int dst:g[cur]) {if (dst==par) continue;if (col[dst]!=0) {System.out.println("Yes");System.exit(0);}if (col[dst]==0) dfs_bi(dst,cur,g,col);}col[cur]=2;}void run() {FastScanner sc=new FastScanner();PrintWriter pw=new PrintWriter(System.out);int N=sc.nextInt();int M=sc.nextInt();ArrayList<Integer>[] g=new ArrayList[N];ArrayList<Integer>[] g2=new ArrayList[N];DJSet ds=new DJSet(N);int[] a=new int[M];int[] b=new int[M];int[] c=new int[M];for (int i=0;i<N;++i) g[i]=new ArrayList<>();for (int i=0;i<N;++i) g2[i]=new ArrayList<>();for (int i=0;i<M;++i) {a[i]=sc.nextInt();b[i]=sc.nextInt();c[i]=sc.nextInt();--a[i];--b[i];if (c[i]==1) { // big[a[i]].add(b[i]);g[b[i]].add(a[i]);ds.setUnion(a[i], b[i]);}}int[] col=new int[N];for (int i=0;i<N;++i) {if (col[i]==0) dfs_bi(i,-1,g,col);}for (int i=0;i<M;++i) {if (c[i]==2) { // uniif (ds.equiv(a[i], b[i])) {System.out.println("Yes");return;}g2[ds.root(a[i])].add(ds.root(b[i]));}}Arrays.fill(col, 0);dfs_uni(ds.root(0),-1,g2,col);for (int i=0;i<N;++i) {if (i==ds.root(i) && col[i]==0) dfs_uni(ds.root(i), -1, g2, col);}pw.println("No");pw.close();}void tr(Object...objects) {System.out.println(Arrays.deepToString(objects));}public static void main(String[] args) {new Main().run();}}class FastScanner {private final InputStream in = System.in;private final byte[] buffer = new byte[1024];private int ptr = 0;private int buflen = 0;private boolean hasNextByte() {if (ptr < buflen) {return true;}else{ptr = 0;try {buflen = in.read(buffer);} catch (IOException e) {e.printStackTrace();}if (buflen <= 0) {return false;}}return true;}private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}private void skipUnprintable() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;}public boolean hasNext() { skipUnprintable(); return hasNextByte();}public String next() {if (!hasNext()) throw new NoSuchElementException();StringBuilder sb = new StringBuilder();int b = readByte();while(isPrintableChar(b)) {sb.appendCodePoint(b);b = readByte();}return sb.toString();}public long nextLong() {if (!hasNext()) throw new NoSuchElementException();long n = 0;boolean minus = false;int b = readByte();if (b == '-') {minus = true;b = readByte();}if (b < '0' || '9' < b) {throw new NumberFormatException();}while(true){if ('0' <= b && b <= '9') {n *= 10;n += b - '0';}else if(b == -1 || !isPrintableChar(b)){return minus ? -n : n;}else{throw new NumberFormatException();}b = readByte();}}public int nextInt() {return (int)nextLong();}}