没看清题号，TimeLimit。啊。  直接计算次数即可。

代码 ：

import java.util.*;

public class Main1954 {

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int t = scan.nextInt();
		while(t-- > 0) {
			int[] a = new int[16];
			int n = scan.nextInt();
			for(int i=0; i<n; i++) {
				a[i] = scan.nextInt();
			}
			int flag = 0;
			for(int k=0; k<200; k++) {
				int cnt = 0;
				int[] b = new int[16];
				for(int i=0; i<n; i++) {
					if(i == n-1) 
						b[i] = Math.abs(a[n-1]-a[0]);
					else
					    b[i] = Math.abs(a[i] - a[i+1]);
					if(b[i] == 0)
						cnt ++;
				}
				if(cnt == n) {
                	flag = 1;
                	break;
                }
				a = b;
				//System.out.println(a[0] + " " + a[1] + " " + a[2] + " " + a[3]);
			}
			if(flag == 1)
				System.out.println("ZERO");
			else
				System.out.println("LOOP");
			
		}

	}

}

UVa 1594 - Ducci Sequence