package main

import "fmt"

func main() {
	var A, B float64
	fmt.Scan(&A, &B)

	x := float64(30*(int(A)%12)) + B/2
	y := 6 * B

	if int(x)%360 == int(y)%360 {
		fmt.Println("0")
	} else {
		if x < y {
			x += 360
		}
		ans := 60 * (2*x - 2*y) / 11
		fmt.Println(int(ans))
	}
}