#include <iostream>
#include <map>
#include <set>
#include <algorithm>
#include <vector>
using namespace std;

int n;
int a[100000],b[100000];

int main()
{
	ios::sync_with_stdio(false);

	cin >> n;

	for (int i = 1; i <= n; i++) {
		cin >> a[i];
		
	}
	int sum = 0;
	for (int i = n; i >=1; i--) {
		
		cin >> b[i];
		

	}
	int ct = 0;
	for (int i = 1; i <= n; i++) {
		if (a[i] !=b[i]-ct){
			sum += n - i;
			ct++;
		}
	}

	cout << sum;

    return 0;
}