halloween.java

Ulm大学2007年竞赛题和解题报告

// Author: Adrian Kuegel

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

public class halloween {
	public static void main(String [] args) throws Exception {
		Scanner in = new Scanner(new File("halloween.in"));
		while(true) {
			int c = in.nextInt();
			int n = in.nextInt();
			if (c == 0 && n == 0)
				break;
			int [] ind = new int[c];
			Arrays.fill(ind,-1);
			int sum = 0;
			ind[0] = 0;
			for (int i=0; i<n; ++i) {
				int a = in.nextInt();
				sum = (sum+a)%c;
				if (ind[sum] >= 0) {
					for (int j=ind[sum]; j<=i; ++j) {
						System.out.print(j+1);
						if (j<i) System.out.print(" ");
					}
					System.out.println("");
					for (i++; i<n; ++i)
						a = in.nextInt();
					break;
				}
				ind[sum] = i+1;
			}
		}
	}
}