#include <iostream>

int main() {
	int Entry = 3;
	int Start;
	int End;
	
	std::cin >> Start >> End;

	for (int i = Start; i <= End; i++) {
		for (int j = 23; j <= 25; j++) {
			if (i == j)Entry--;
		}
	}

	std::cout << Entry << std::endl;

	return 0;
}