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());
        int a[]=new int[n],b,i; long ans=0;
        String s[]=bu.readLine().split(" ");
        TreeSet<Integer> ts=new TreeSet<>();
        for(i=0;i<n;i++)
        {
            a[i]=Integer.parseInt(s[i]);
            ts.add(i+1);
        }

        for(i=n-1;i>=0;i--)
        if(ts.higher(a[i])!=null)
        {
            int del=ts.higher(a[i]);
            ts.remove(del);
            ans+=i+1;
        }
        else if(ts.contains(a[i])) ts.remove(a[i]);
        else ans-=i+1;
        System.out.println(ans);
    }
}