#include <bits/stdc++.h>
using namespace std;

int main()
{
	int a, b, ans = 0;
	scanf("%d%d", &a, &b);
	int t = b, len = 0;
	while (t)
	{
		t /= 10;
		len++;
	}
	for (int i = 1; i < len; i++)
		for (int j = 1; j <= i; j++)
			ans += j;
	t = a, len = 0;
	while (t)
	{
		t /= 10;
		len++;
	}
	for (int i = 1; i < len; i++)
		for (int j = 1; j <= i; j++)
			ans -= j;
	printf("%d", ans);
	return 0;
}