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

class Main
{
    public static void main(String args[])throws Exception
    {
        BufferedReader bu=new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb=new StringBuilder();
        int n=Integer.parseInt(bu.readLine());
        String s[]=bu.readLine().split(" ");
        int i,a[]=new int[n];
        for(i=0;i<n;i++) a[i]=Integer.parseInt(s[i]);

        int dp[]=new int[n]; long ans=0;
        for(i=n-2;i>=0;i--)
        {
            if(a[i]!=a[i+1]) dp[i]=dp[i+1]+1;
            else dp[i]=1;
            if(a[i]==1) ans+=dp[i];
        }
        System.out.println(ans);
    }
}