#include <iostream>

using namespace std;
void countDistinct(char symbols[], int i, int j) {

	int count = 0;
	bool different = false;
	for (int k = i; k <= j; k++)
	{
		for (int p = i; p <= j; p++)
		{

			if (symbols[k] != symbols[p]) {
				different = true;
			}

		if (different == true) {
			count++;
			different = false;
		}
	}

	cout<<count;
}
int main() {
	char symbols[]= { 'n', 'a', 'b', 'a', 'b', 'a', 't', 'i', 'h', 'v', 'u', 'r', '4', 'i', 'l', 'o', 't', 'o' };

	int i, j;
	cin >> i >> j;

	if (j < i)
		std::cout << "Wrong input!" << std::endl;
	//if (i == j)
	//	std::cout << 1 << std::endl;

	countDistinct(symbols, i, j);

	return 0;
}