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

public class gergovia {
	public static void main(String [] args) throws Exception {
		Scanner in = new Scanner(new File("gergovia.in"));
		int n;
		while( (n = in.nextInt()) > 0) {
			long sum = 0;
			long result = 0;
			for (int i=0; i<n; i++) {
				sum += in.nextInt();
				result += Math.abs(sum);
			}
			System.out.println(result);
		}
	}
}