import java.util.Arrays; public class Main { private static void solve() { int n = ni(); int[] a = na(n); int[] b = new int[n]; int[] inva = new int[n]; int[] invb = new int[n]; for (int i = 0; i < n; i++) { b[i] = -a[i]; inva[n - i - 1] = a[i]; invb[n - i - 1] = b[i]; } int[] al1 = lis(a); int[] bl1 = lis(b); int[] al2 = lis(inva); int[] bl2 = lis(invb); for (int i = 0, j = n - 1; i < j; i++, j--) { { int tmp = al2[i]; al2[i] = al2[j]; al2[j] = tmp; } { int tmp = bl2[i]; bl2[i] = bl2[j]; bl2[j] = tmp; } } int ret = 0; for (int i = 0; i < n; i++) { ret = Math.max(ret, Math.min(bl1[i], bl2[i]) - 1); ret = Math.max(ret, Math.min(al1[i], al2[i]) - 1); } System.out.println(ret); } public static int[] lis(int[] in) { int n = in.length; int[] ret = new int[n]; int now = 0; int[] h = new int[n + 1]; Arrays.fill(h, Integer.MIN_VALUE / 2); for (int i = 0; i < n; i++) { int ind = Arrays.binarySearch(h, 0, now + 1, in[i]); if (ind < 0) { ind = -ind - 2; h[ind + 1] = in[i]; if (ind >= now) now++; } ret[i] = now; } return ret; } public static void main(String[] args) { new Thread(null, new Runnable() { @Override public void run() { long start = System.currentTimeMillis(); String debug = args.length > 0 ? args[0] : null; if (debug != null) { try { is = java.nio.file.Files.newInputStream(java.nio.file.Paths.get(debug)); } catch (Exception e) { throw new RuntimeException(e); } } reader = new java.io.BufferedReader(new java.io.InputStreamReader(is), 32768); solve(); out.flush(); tr((System.currentTimeMillis() - start) + "ms"); } }, "", 64000000).start(); } private static java.io.InputStream is = System.in; private static java.io.PrintWriter out = new java.io.PrintWriter(System.out); private static java.util.StringTokenizer tokenizer = null; private static java.io.BufferedReader reader; public static String next() { while (tokenizer == null || !tokenizer.hasMoreTokens()) { try { tokenizer = new java.util.StringTokenizer(reader.readLine()); } catch (Exception e) { throw new RuntimeException(e); } } return tokenizer.nextToken(); } private static double nd() { return Double.parseDouble(next()); } private static long nl() { return Long.parseLong(next()); } private static int[] na(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) a[i] = ni(); return a; } private static char[] ns() { return next().toCharArray(); } private static long[] nal(int n) { long[] a = new long[n]; for (int i = 0; i < n; i++) a[i] = nl(); return a; } private static int[][] ntable(int n, int m) { int[][] table = new int[n][m]; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { table[i][j] = ni(); } } return table; } private static int[][] nlist(int n, int m) { int[][] table = new int[m][n]; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { table[j][i] = ni(); } } return table; } private static int ni() { return Integer.parseInt(next()); } private static void tr(Object... o) { if (is != System.in) System.out.println(java.util.Arrays.deepToString(o)); } }