Submission #337883

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Source Code Expand

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Set;
import java.util.SortedMap;
import java.util.StringTokenizer;
import java.util.TreeMap;
import java.util.TreeSet;

public class Main {
	
	public static boolean dfs(final int n, final int deep, final int using, final int index, String[] inputs, boolean[] used){
		if(deep >= n){
			return true;
		}
		
		for(int next = 0; next < n; next++){
			final int next_index = index + 1;

			if(used[next]){
				continue;
			}
			
			//System.out.println(deep + " : " + inputs[using] + "[" + index + "] " + " -> " + inputs[next] + "[" + next_index + "]");
			if(inputs[next].length() <= next_index){
				continue;
			}else if(inputs[next].charAt(next_index) != inputs[using].charAt(index)){
				continue;
			}
			
			used[next] = true;
			if(dfs(n, deep + 1, next, next_index, inputs, used)){
				return true;
			}
			used[next] = false;
		}
		
		return false;
	}
	
	public static void main(String[] args) throws IOException {
		Scanner sc = new Scanner(System.in);
	
		final int n = sc.nextInt();
		String[] inputs = new String[n];
		for(int i = 0; i < n; i++){
			inputs[i] = sc.next();
		}
		
		boolean[] used = new boolean[n];
		for(int last = 0; last < n; last++){
			final int size = inputs[last].length();
			used[last] = true;
			
			for(int index = 0; index < size; index++){
				
				if(dfs(n, 1, last, index, inputs, used)){
					System.out.println("YES");
					return;
				}
			}
			
			used[last] = false;
		}
		
		System.out.println("NO");
	}

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

}

Submission Info

Judge Result