import java.util.*; import java.io.*; public class Main {; public static void main(String[] args) throws Exception { FastScanner sc = new FastScanner(System.in); PrintWriter pw = new PrintWriter(System.out); StringBuilder sb = new StringBuilder(); int a = sc.nextInt(); int b = sc.nextInt(); double h = ((a*30d+b*0.5d)/360d)%1; double m = (b*6d/360d)%1; //pw.println(h + " " + m); int ans = 0; if(h >= m){ ans = (int)((h-m)/5.5d*360d)*60; }else{ int nextH = (a+1)%12; ans += (60-b)*60; int rem = (int)(nextH*30d/5.5d*60d); ans += rem; } pw.println(ans); pw.flush(); } static class GeekInteger { public static void save_sort(int[] array) { shuffle(array); Arrays.sort(array); } public static int[] shuffle(int[] array) { int n = array.length; Random random = new Random(); for (int i = 0, j; i < n; i++) { j = i + random.nextInt(n - i); int randomElement = array[j]; array[j] = array[i]; array[i] = randomElement; } return array; } } } class FastScanner { private BufferedReader reader = null; private StringTokenizer tokenizer = null; public FastScanner(InputStream in) { reader = new BufferedReader(new InputStreamReader(in)); tokenizer = null; } public String next() { if (tokenizer == null || !tokenizer.hasMoreTokens()) { try { tokenizer = new StringTokenizer(reader.readLine()); } catch (IOException e) { throw new RuntimeException(e); } } return tokenizer.nextToken(); } public String nextLine() { if (tokenizer == null || !tokenizer.hasMoreTokens()) { try { return reader.readLine(); } catch (IOException e) { throw new RuntimeException(e); } } return tokenizer.nextToken("\n"); } public long nextLong() { return Long.parseLong(next()); } public int nextInt() { return Integer.parseInt(next()); } public double nextDouble() { return Double.parseDouble(next()); } public String[] nextArray(int n) { String[] a = new String[n]; for (int i = 0; i < n; i++) a[i] = next(); return a; } public int[] nextIntArray(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) a[i] = nextInt(); return a; } public long[] nextLongArray(int n) { long[] a = new long[n]; for (int i = 0; i < n; i++) a[i] = nextLong(); return a; } }