結果

問題 No.2464 To DAG
ユーザー uwiuwi
提出日時 2023-09-08 22:17:06
言語 Java21
(openjdk 21)
結果
TLE  
実行時間 -
コード長 17,638 bytes
コンパイル時間 5,735 ms
コンパイル使用メモリ 94,420 KB
実行使用メモリ 145,920 KB
最終ジャッジ日時 2024-06-26 15:23:01
合計ジャッジ時間 11,499 ms
ジャッジサーバーID
（参考情報） 		judge2 / judge1
このコードへのチャレンジ
（要ログイン）

テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 93 ms
45,668 KB
testcase_01 AC 103 ms
40,656 KB
testcase_02 AC 637 ms
139,692 KB
testcase_03 TLE -
testcase_04 -- -
testcase_05 -- -
testcase_06 -- -
testcase_07 -- -
testcase_08 -- -
testcase_09 -- -
testcase_10 -- -
testcase_11 -- -
testcase_12 -- -
testcase_13 -- -
testcase_14 -- -
testcase_15 -- -
testcase_16 -- -
testcase_17 -- -
testcase_18 -- -
testcase_19 -- -
testcase_20 -- -
testcase_21 -- -
testcase_22 -- -
testcase_23 -- -
testcase_24 -- -
testcase_25 -- -
testcase_26 -- -
testcase_27 -- -
testcase_28 -- -
testcase_29 -- -
testcase_30 -- -
testcase_31 -- -
testcase_32 -- -
testcase_33 -- -
testcase_34 -- -
testcase_35 -- -
testcase_36 -- -
testcase_37 -- -
testcase_38 -- -
testcase_39 -- -
testcase_40 -- -
権限があれば一括ダウンロードができます

ソースコード

diff # 

package contest230908;
import java.io.*;
import java.util.*;
import java.util.function.IntUnaryOperator;
import java.util.function.LongUnaryOperator;

public class E {
	InputStream is;
	FastWriter out;

	String INPUT = "";

	public void solve()
	{
		int n = ni();
		int m = ni();
		int[][] es = nmi(m, 2);
		int[] indeg = new int[n];
		int[] outdeg = new int[n];
		for(int i = 0;i < m;i++){
			int u = es[i][0] - 1;
			int v = es[i][1] - 1;
			indeg[v]++;
			outdeg[u]++;
		}
		List<Edge> eds = new ArrayList<>();
		int src = n, sink = n+1;
		for(int i = 0;i < n;i++){
			if(indeg[i] > outdeg[i]){
				eds.add(new Edge(i, sink, indeg[i]-outdeg[i]));
			}else{
				eds.add(new Edge(src, i, outdeg[i]-indeg[i]));
			}
		}
		for(int i = 0;i < m;i++){
			int u = es[i][0] - 1;
			int v = es[i][1] - 1;
			eds.add(new Edge(u, v, 1));
		}
		Edge[][] g = compileWD(n+2, eds);
		long flow = maximumFlowDinicNoRec(g, src, sink);
		List<int[]> ans = new ArrayList<>();
		for(Edge e : eds){
//			if(!e.cloned) {
//				out.print(e.from + " ");
//				out.print(e.to + " ");
//				out.print(e.flow + "\n");
//			}
//			tr(e.from, e.to, e.flow);
			if(!e.cloned && e.from < src && e.to < src && e.flow > 0){
				ans.add(new int[]{e.from+1, e.to+1});
			}
		}
		out.println(n + " " + ans.size());
		for(int[] e : ans){
			out.println(e[0] + " " + e[1]);
		}
	}

	public static class Edge
	{
		public int from, to;
		public long capacity;
		public long flow;
		public Edge complement;
		public boolean cloned;

		public Edge(int from, int to, long capacity) {
			this.from = from;
			this.to = to;
			this.capacity = capacity;
		}
	}

	public static void reset(Edge[][] g)
	{
		for(Edge[] row : g){
			for(Edge e : row){
				e.flow = e.cloned ? e.capacity : 0;
			}
		}
	}

	public static Edge[][] compileWD(int n, List<Edge> edges)
	{
		Edge[][] g = new Edge[n][];
		// cloning
		for(int i = edges.size()-1;i >= 0;i--){
			Edge origin = edges.get(i);
			Edge clone = new Edge(origin.to, origin.from, origin.capacity);
			clone.flow = origin.capacity;
			clone.complement = origin;
			clone.cloned = true;
			origin.complement = clone;
			edges.add(clone);
		}

		int[] p = new int[n];
		for(Edge e : edges)p[e.from]++;
		for(int i = 0;i < n;i++)g[i] = new Edge[p[i]];
		for(Edge e : edges)g[e.from][--p[e.from]] = e;
		return g;
	}

	public static Edge[][] compileWU(int n, List<Edge> edges)
	{
		Edge[][] g = new Edge[n][];
		// cloning
		for(int i = edges.size()-1;i >= 0;i--){
			Edge origin = edges.get(i);
			Edge clone = new Edge(origin.to, origin.from, origin.capacity*2);
			origin.flow = origin.capacity;
			clone.flow = origin.capacity;
			clone.complement = origin;
			clone.cloned = true;
			origin.complement = clone;
			origin.capacity *= 2;
			edges.add(clone);
		}

		int[] p = new int[n];
		for(Edge e : edges)p[e.from]++;
		for(int i = 0;i < n;i++)g[i] = new Edge[p[i]];
		for(Edge e : edges)g[e.from][--p[e.from]] = e;
		return g;
	}

	public static long maximumFlowDinic(Edge[][] g, int source, int sink)
	{
		int n = g.length;
		int[] d = new int[n];
		int[] q = new int[n];
		long ret = 0;
		while(true){
			Arrays.fill(d, -1);
			q[0] = source;
			int r = 1;
			d[source] = 0;

			for(int v = 0;v < r;v++){
				int cur = q[v];
				for(Edge ne : g[cur]){
					if(d[ne.to] == -1 && ne.capacity - ne.flow > 0) {
						q[r++] = ne.to;
						d[ne.to] = d[cur] + 1;
					}
				}
			}
			if(d[sink] == -1)break;
			int[] sp = new int[n];
			for(int i = 0;i < n;i++)sp[i] = g[i].length - 1;
			ret += dfsDinic(d, g, sp, source, sink, Long.MAX_VALUE);
		}

		return ret;
	}

	private static long dfsDinic(int[] d, Edge[][] g, int[] sp, int cur, int sink, long min)
	{
		if(cur == sink)return min;
		long left = min;
		for(int i = sp[cur];i >= 0;i--){
			Edge ne = g[cur][i];
			if(d[ne.to] == d[cur]+1 && ne.capacity - ne.flow > 0){
				long fl = dfsDinic(d, g, sp, ne.to, sink, Math.min(left, ne.capacity - ne.flow));
				if(fl > 0){
					left -= fl;
					ne.flow += fl;
					ne.complement.flow -= fl;
					if(left == 0){
						sp[cur] = i;
						return min;
					}
				}
			}
		}
		sp[cur] = -1;
		return min-left;
	}

	public static long maximumFlowDinicNoRec(Edge[][] g, int source, int sink)
	{
		int n = g.length;
		int[] d = new int[n]; // distance
		int[] q = new int[n]; // queue for BFS
		long ret = 0;
		int[] stack = new int[n];
		long[] lefts = new long[n]; // left to flow
		long[] parflow = new long[n];
		int[] probe = new int[n]; // search pointer
		while(true){
			// BFS
			Arrays.fill(d, -1);
			q[0] = source;
			int r = 1;
			d[source] = 0;
			for(int v = 0;v < r;v++){
				int cur = q[v];
				for(Edge ne : g[cur]){
					if(d[ne.to] == -1 && ne.capacity - ne.flow > 0) {
						q[r++] = ne.to;
						d[ne.to] = d[cur] + 1;
					}
				}
			}
			if(d[sink] == -1)break;

			// DFS
			for(int i = 0;i < n;i++)probe[i] = g[i].length-1;
			int sp = 0;
			stack[sp] = source;
			lefts[sp] = Long.MAX_VALUE / 10;
			parflow[sp] = 0;
			sp++;
			long delta = 0;
			boolean down = true;
			while(sp > 0){
				int cur = stack[sp-1];
				long left = lefts[sp-1];
				if(cur == sink){
					delta += left;
					parflow[sp-1] = left;
					sp--;
					down = false;
					continue;
				}
				if(!down){
					if(parflow[sp] > 0){
						lefts[sp-1] -= parflow[sp];
						left = lefts[sp-1];
						Edge ne = g[cur][probe[cur]];
						ne.flow += parflow[sp];
						ne.complement.flow -= parflow[sp];
						parflow[sp-1] += parflow[sp];
					}
					if(left > 0)probe[cur]--;
				}
				if(left > 0 && probe[cur] >= 0){
					down = true;
					Edge ne = g[cur][probe[cur]];
					if(d[ne.to] == d[cur]+1 && ne.capacity - ne.flow > 0){
						lefts[sp] = Math.min(left, ne.capacity - ne.flow);
						stack[sp] = ne.to;
						parflow[sp] = 0;
						sp++;
					}else{
						probe[cur]--;
					}
				}else{
					down = false;
					sp--;
				}
			}
			ret += delta;
		}
		return ret;
	}

	/**
	 * sourceに一番近い最小カットを返す。
	 * source側がtrue, sink側がfalse
	 *
	 * @param g
	 * @param source
	 * @param sink
	 * @return
	 */
	public static boolean[] restoreCutPessimistically(Edge[][] g, int src)
	{
		int n = g.length;
		boolean[] ved = new boolean[n];
		ved[src] = true;
		int[] q = new int[n];
		int p = 0;
		q[p++] = src;
		for(int r = 0;r < p;r++){
			int cur = q[r];
			for(Edge e : g[cur]){
				assert e.from == cur;
				if(e.flow < e.capacity && !ved[e.to]){
					ved[e.to] = true;
					q[p++] = e.to;
				}
			}
		}
		return ved;
	}


	public static void main(String[] args) {
		new E().run();
	}

	public void run()
	{
		long S = System.currentTimeMillis();
		is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes());
		out = new FastWriter(System.out);

		solve();
		out.flush();
		long G = System.currentTimeMillis();
		tr(G-S+"ms");
		//		Thread t = new Thread(null, null, "~", Runtime.getRuntime().maxMemory()){
		//			@Override
		//			public void run() {
		//				long s = System.currentTimeMillis();
		//				solve();
		//				out.flush();
		//				if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms");
		//			}
		//		};
		//		t.start();
		//		t.join();
	}

	private boolean eof()
	{
		if(lenbuf == -1)return true;
		int lptr = ptrbuf;
		while(lptr < lenbuf)if(!isSpaceChar(inbuf[lptr++]))return false;

		try {
			is.mark(1000);
			while(true){
				int b = is.read();
				if(b == -1){
					is.reset();
					return true;
				}else if(!isSpaceChar(b)){
					is.reset();
					return false;
				}
			}
		} catch (IOException e) {
			return true;
		}
	}

	private final byte[] inbuf = new byte[1024];
	public int lenbuf = 0, ptrbuf = 0;

	private int readByte()
	{
		if(lenbuf == -1)throw new InputMismatchException();
		if(ptrbuf >= lenbuf){
			ptrbuf = 0;
			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
			if(lenbuf <= 0)return -1;
		}
		return inbuf[ptrbuf++];
	}

	private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
	//	private boolean isSpaceChar(int c) { return !(c >= 32 && c <= 126); }
	private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }

	private double nd() { return Double.parseDouble(ns()); }
	private char nc() { return (char)skip(); }

	private String ns()
	{
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while(!(isSpaceChar(b))){
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}

	private char[] ns(int n)
	{
		char[] buf = new char[n];
		int b = skip(), p = 0;
		while(p < n && !(isSpaceChar(b))){
			buf[p++] = (char)b;
			b = readByte();
		}
		return n == p ? buf : Arrays.copyOf(buf, p);
	}

	private char[][] nm(int n, int m)
	{
		char[][] map = new char[n][];
		for(int i = 0;i < n;i++)map[i] = ns(m);
		return map;
	}

	private int[][] nmi(int n, int m)
	{
		int[][] map = new int[n][];
		for(int i = 0;i < n;i++)map[i] = na(m);
		return map;
	}

	private int[] na(int n)
	{
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		return a;
	}

	private long[] nal(int n)
	{
		long[] a = new long[n];
		for(int i = 0;i < n;i++)a[i] = nl();
		return a;
	}

	private int ni()
	{
		int num = 0, b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}

		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}

	private long nl()
	{
		long num = 0;
		int b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}

		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}

	public static class FastWriter
	{
		private static final int BUF_SIZE = 1<<13;
		private final byte[] buf = new byte[BUF_SIZE];
		private final OutputStream out;
		private int ptr = 0;

		private FastWriter(){out = null;}

		public FastWriter(OutputStream os)
		{
			this.out = os;
		}

		public FastWriter(String path)
		{
			try {
				this.out = new FileOutputStream(path);
			} catch (FileNotFoundException e) {
				throw new RuntimeException("FastWriter");
			}
		}

		public FastWriter write(byte b)
		{
			buf[ptr++] = b;
			if(ptr == BUF_SIZE)innerflush();
			return this;
		}

		public FastWriter write(char c)
		{
			return write((byte)c);
		}

		public FastWriter write(char[] s)
		{
			for(char c : s){
				buf[ptr++] = (byte)c;
				if(ptr == BUF_SIZE)innerflush();
			}
			return this;
		}

		public FastWriter write(String s)
		{
			s.chars().forEach(c -> {
				buf[ptr++] = (byte)c;
				if(ptr == BUF_SIZE)innerflush();
			});
			return this;
		}

		private static int countDigits(int l) {
			if (l >= 1000000000) return 10;
			if (l >= 100000000) return 9;
			if (l >= 10000000) return 8;
			if (l >= 1000000) return 7;
			if (l >= 100000) return 6;
			if (l >= 10000) return 5;
			if (l >= 1000) return 4;
			if (l >= 100) return 3;
			if (l >= 10) return 2;
			return 1;
		}

		public FastWriter write(int x)
		{
			if(x == Integer.MIN_VALUE){
				return write((long)x);
			}
			if(ptr + 12 >= BUF_SIZE)innerflush();
			if(x < 0){
				write((byte)'-');
				x = -x;
			}
			int d = countDigits(x);
			for(int i = ptr + d - 1;i >= ptr;i--){
				buf[i] = (byte)('0'+x%10);
				x /= 10;
			}
			ptr += d;
			return this;
		}

		private static int countDigits(long l) {
			if (l >= 1000000000000000000L) return 19;
			if (l >= 100000000000000000L) return 18;
			if (l >= 10000000000000000L) return 17;
			if (l >= 1000000000000000L) return 16;
			if (l >= 100000000000000L) return 15;
			if (l >= 10000000000000L) return 14;
			if (l >= 1000000000000L) return 13;
			if (l >= 100000000000L) return 12;
			if (l >= 10000000000L) return 11;
			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 FastWriter write(long x)
		{
			if(x == Long.MIN_VALUE){
				return write("" + x);
			}
			if(ptr + 21 >= BUF_SIZE)innerflush();
			if(x < 0){
				write((byte)'-');
				x = -x;
			}
			int d = countDigits(x);
			for(int i = ptr + d - 1;i >= ptr;i--){
				buf[i] = (byte)('0'+x%10);
				x /= 10;
			}
			ptr += d;
			return this;
		}

		public FastWriter write(double x, int precision)
		{
			if(x < 0){
				write('-');
				x = -x;
			}
			x += Math.pow(10, -precision)/2;
			//		if(x < 0){ x = 0; }
			write((long)x).write(".");
			x -= (long)x;
			for(int i = 0;i < precision;i++){
				x *= 10;
				write((char)('0'+(int)x));
				x -= (int)x;
			}
			return this;
		}

		public FastWriter writeln(char c){ return write(c).writeln(); }
		public FastWriter writeln(int x){ return write(x).writeln(); }
		public FastWriter writeln(long x){ return write(x).writeln(); }
		public FastWriter writeln(double x, int precision){ return write(x, precision).writeln(); }

		public FastWriter write(int... xs)
		{
			boolean first = true;
			for(int x : xs) {
				if (!first) write(' ');
				first = false;
				write(x);
			}
			return this;
		}

		public FastWriter write(long... xs)
		{
			boolean first = true;
			for(long x : xs) {
				if (!first) write(' ');
				first = false;
				write(x);
			}
			return this;
		}

		public FastWriter write(IntUnaryOperator f, int... xs)
		{
			boolean first = true;
			for(int x : xs) {
				if (!first) write(' ');
				first = false;
				write(f.applyAsInt(x));
			}
			return this;
		}

		public FastWriter write(LongUnaryOperator f, long... xs)
		{
			boolean first = true;
			for(long x : xs) {
				if (!first) write(' ');
				first = false;
				write(f.applyAsLong(x));
			}
			return this;
		}

		public FastWriter writeln()
		{
			return write((byte)'\n');
		}

		public FastWriter writeln(int... xs) { return write(xs).writeln(); }
		public FastWriter writeln(long... xs) { return write(xs).writeln(); }
		public FastWriter writeln(IntUnaryOperator f, int... xs) { return write(f, xs).writeln(); }
		public FastWriter writeln(LongUnaryOperator f, long... xs) { return write(f, xs).writeln(); }
		public FastWriter writeln(char[] line) { return write(line).writeln(); }
		public FastWriter writeln(char[]... map) { for(char[] line : map)write(line).writeln();return this; }
		public FastWriter writeln(String s) { return write(s).writeln(); }

		private void innerflush()
		{
			try {
				out.write(buf, 0, ptr);
				ptr = 0;
			} catch (IOException e) {
				throw new RuntimeException("innerflush");
			}
		}

		public void flush()
		{
			innerflush();
			try {
				out.flush();
			} catch (IOException e) {
				throw new RuntimeException("flush");
			}
		}

		public FastWriter print(byte b) { return write(b); }
		public FastWriter print(char c) { return write(c); }
		public FastWriter print(char[] s) { return write(s); }
		public FastWriter print(String s) { return write(s); }
		public FastWriter print(int x) { return write(x); }
		public FastWriter print(long x) { return write(x); }
		public FastWriter print(double x, int precision) { return write(x, precision); }
		public FastWriter println(char c){ return writeln(c); }
		public FastWriter println(int x){ return writeln(x); }
		public FastWriter println(long x){ return writeln(x); }
		public FastWriter println(double x, int precision){ return writeln(x, precision); }
		public FastWriter print(int... xs) { return write(xs); }
		public FastWriter print(long... xs) { return write(xs); }
		public FastWriter print(IntUnaryOperator f, int... xs) { return write(f, xs); }
		public FastWriter print(LongUnaryOperator f, long... xs) { return write(f, xs); }
		public FastWriter println(int... xs) { return writeln(xs); }
		public FastWriter println(long... xs) { return writeln(xs); }
		public FastWriter println(IntUnaryOperator f, int... xs) { return writeln(f, xs); }
		public FastWriter println(LongUnaryOperator f, long... xs) { return writeln(f, xs); }
		public FastWriter println(char[] line) { return writeln(line); }
		public FastWriter println(char[]... map) { return writeln(map); }
		public FastWriter println(String s) { return writeln(s); }
		public FastWriter println() { return writeln(); }
	}

	public static void trnz(int... o)
	{
		for(int i = 0;i < o.length;i++)if(o[i] != 0)System.out.print(i+":"+o[i]+" ");
		System.out.println();
	}

	// print ids which are 1
	public static void trt(long... o)
	{
		Queue<Integer> stands = new ArrayDeque<>();
		for(int i = 0;i < o.length;i++){
			for(long x = o[i];x != 0;x &= x-1)stands.add(i<<6|Long.numberOfTrailingZeros(x));
		}
		System.out.println(stands);
	}

	public static void tf(boolean... r)
	{
		for(boolean x : r)System.out.print(x?'#':'.');
		System.out.println();
	}

	public static void tf(boolean[]... b)
	{
		for(boolean[] r : b) {
			for(boolean x : r)System.out.print(x?'#':'.');
			System.out.println();
		}
		System.out.println();
	}

	public void tf(long[]... b)
	{
		if(INPUT.length() != 0) {
			for (long[] r : b) {
				for (long x : r) {
					for (int i = 0; i < 64; i++) {
						System.out.print(x << ~i < 0 ? '#' : '.');
					}
				}
				System.out.println();
			}
			System.out.println();
		}
	}

	public void tf(long... b)
	{
		if(INPUT.length() != 0) {
			for (long x : b) {
				for (int i = 0; i < 64; i++) {
					System.out.print(x << ~i < 0 ? '#' : '.');
				}
			}
			System.out.println();
		}
	}

	private void tr(Object... o) { if(INPUT.length() != 0)System.out.println(Arrays.deepToString(o)); }
}
0