Submission #94340

#	Time	Username	Problem	Language	Result	Execution time	Memory
94340		zeyad49	Savez (COCI15_savez)	Java	120 / 120	550 ms	51504 KiB

savez

import java.io.*;
import java.util.*;

class savez{

	
	static int n;
	
	static int MOD=(int)1e9+9,p=31,maxN=(int)2e6+5;;
	
	public static void main(String[] args) throws IOException {
		Scanner sc=new Scanner();
		PrintWriter out=new PrintWriter(System.out);
		
		n=sc.nextInt();
		int ans=1;
		HashMap<Integer,Integer> map=new HashMap();
		for(int i=0;i<n;i++) {
			char []s=sc.next().toCharArray();
			int len=s.length;
			int []hash=new int [len];
			long pow=1;
			long last=0;
			for(int j=0;j<len;j++) {
				last=last+(s[j]-'A'+1)*1l*pow;
				last%=MOD;
				hash[j]=(int)last;
				pow=pow*p%MOD;
			}
			
			int dp=1;
			pow=1;
			for(int prefix=len;prefix>0;prefix--) {
				int preHash=hash[prefix-1],sufHash=hash[len-1]-(prefix==len?0:hash[len-1-prefix]);
				if(sufHash<0)
					sufHash+=MOD;
			
				
				if(sufHash==(preHash*1l*pow%MOD))
					dp=Math.max(dp, 1+map.getOrDefault(preHash, 0));
				pow=pow*p%MOD;
			}
			map.put(hash[len-1], dp);
			ans=Math.max(ans, dp);
		}
		out.println(ans);
		
		
		
		out.close();

	}
	
	static class Scanner
	{
		BufferedReader br;
		StringTokenizer st;
		Scanner(){
			br=new BufferedReader(new InputStreamReader(System.in));
		}
		Scanner(String fileName) throws FileNotFoundException{
			br=new BufferedReader(new FileReader(fileName));
		}
		String next() throws IOException {
			while(st==null || !st.hasMoreTokens())
				st=new StringTokenizer(br.readLine());
			return st.nextToken();
		}
		String nextLine() throws IOException {
			return br.readLine();
		}
		int nextInt() throws IOException{
			return Integer.parseInt(next());
		}
		long nextLong()  throws NumberFormatException, IOException {
			return Long.parseLong(next());
		}
		double nextDouble() throws NumberFormatException, IOException {
			return Double.parseDouble(next());
		}
	}
}

Compilation message (stderr)

Note: savez.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.

• Subtask 1: 12 / 12
• Subtask 2: 12 / 12
• Subtask 3: 12 / 12
• Subtask 4: 12 / 12
• Subtask 5: 12 / 12
• Subtask 6: 12 / 12
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• Subtask 10: 12 / 12