結果

問題 No.468 役に立つ競技プログラミング実践編
コンテスト
ユーザー uafr_cs
提出日時 2017-11-01 23:33:46
言語 Java
(openjdk 23)
結果
AC  
実行時間 1,740 ms / 2,000 ms
コード長 3,962 bytes
コンパイル時間 3,086 ms
コンパイル使用メモリ 87,548 KB
実行使用メモリ 145,056 KB
最終ジャッジ日時 2024-11-22 14:52:02
合計ジャッジ時間 26,423 ms
ジャッジサーバーID
（参考情報） 		judge2 / judge3
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 31
other AC * 6
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 # 

import java.io.BufferedReader;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.StringTokenizer;
import java.util.Map.Entry;
import java.util.Scanner;

public class Main {
	
	public static final long INF = Long.MAX_VALUE / 2 - 1;
	
	public static void main(String[] args) throws IOException {
		Scanner sc = new Scanner(System.in);
		
		final int N = sc.nextInt();
		final int M = sc.nextInt();
		
		ArrayList<HashMap<Integer, Long>> fwd_adj = new ArrayList<HashMap<Integer, Long>>();
		ArrayList<HashMap<Integer, Long>> rev_adj = new ArrayList<HashMap<Integer, Long>>();
		for(int i = 0; i < N; i++){
			fwd_adj.add(new HashMap<Integer, Long>());
			rev_adj.add(new HashMap<Integer, Long>());
		}
		
		int[] in_degs = new int[N];
		int[] out_degs = new int[N];
		for(int i = 0; i < M; i++){
			final int A = sc.nextInt();
			final int B = sc.nextInt();
			final long C = sc.nextLong();
			
			fwd_adj.get(A).put(B, C);
			rev_adj.get(B).put(A, C);
			
			in_degs[B]++;
			out_degs[A]++;
		}
		
		long[] max_path = new long[N];
		long[] rev_max_path = new long[N];
		Arrays.fill(max_path, -1);
		Arrays.fill(rev_max_path, -1);
		max_path[0] = 0;
		
		LinkedList<Integer> queue = new LinkedList<>();
		for(int i = 0; i < N; i++){
			if(in_degs[i] != 0){ continue; }
			queue.add(i);
		}
		while(!queue.isEmpty()){
			final int node = queue.poll();
			
			for(final Entry<Integer, Long> entry : fwd_adj.get(node).entrySet()){
				final int next = entry.getKey();
				final long cost = max_path[node] + entry.getValue();
				
				if(max_path[next] < 0 || max_path[next] < cost){
					max_path[next] = cost;
				}
				
				in_degs[next]--;
				if(in_degs[next] == 0){ queue.add(next); }
			}
		}
		
		rev_max_path[N - 1] = max_path[N - 1];
		for(int i = 0; i < N; i++){
			if(out_degs[i] != 0){ continue; }
			queue.add(i);
		}
		while(!queue.isEmpty()){
			final int node = queue.poll();
			
			for(final Entry<Integer, Long> entry : rev_adj.get(node).entrySet()){
				final int prev = entry.getKey();
				final long cost = rev_max_path[node] - entry.getValue();
				
				if(rev_max_path[prev] < 0 || rev_max_path[prev] > cost){
					rev_max_path[prev] = cost;
				}
				
				out_degs[prev]--;
				if(out_degs[prev] == 0){ queue.add(prev); }
			}
		}
		
		int count = 0;
		for(int i = 0; i < N; i++){
			if(max_path[i] != rev_max_path[i]){
				count++;
			}
		}
		System.out.println(max_path[N-1] + " " + count + "/" + N);
		//System.out.println(Arrays.toString(max_path));
		//System.out.println(Arrays.toString(rev_max_path));
		
	}
	
	public static class Scanner implements Closeable {
		private BufferedReader br;
		private StringTokenizer tok;

		public Scanner(InputStream is) throws IOException {
			br = new BufferedReader(new InputStreamReader(is));
		}

		private void getLine() throws IOException {
			while (!hasNext()) {
				tok = new StringTokenizer(br.readLine());
			}
		}

		private boolean hasNext() {
			return tok != null && tok.hasMoreTokens();
		}

		public String next() throws IOException {
			getLine();
			return tok.nextToken();
		}

		public int nextInt() throws IOException {
			return Integer.parseInt(next());
		}

		public long nextLong() throws IOException {
			return Long.parseLong(next());
		}

		public double nextDouble() throws IOException {
			return Double.parseDouble(next());
		}

		public int[] nextIntArray(int n) throws IOException {
			final int[] ret = new int[n];
			for (int i = 0; i < n; i++) {
				ret[i] = this.nextInt();
			}
			return ret;
		}

		public long[] nextLongArray(int n) throws IOException {
			final long[] ret = new long[n];
			for (int i = 0; i < n; i++) {
				ret[i] = this.nextLong();
			}
			return ret;
		}

		public void close() throws IOException {
			br.close();
		}
	}
}
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