import java.io.*; import java.util.*; public class Main { public static void main(String[] args) throws Exception { Scanner sc = new Scanner(); int n = sc.nextInt(); int[] values = new int[n]; for (int i = 0; i < n; i++) { values[i] = sc.nextInt(); } int idx = n - 1; int ans = n; for (int i = n; i >= 1 && idx >= 0; i--) { while (idx >= 0 && values[idx] != i) { idx--; } if (idx < 0) { break; } idx--; ans--; } System.out.println(ans); } } class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); StringBuilder sb = new StringBuilder(); public Scanner() throws Exception { } public int nextInt() throws Exception { return Integer.parseInt(next()); } public long nextLong() throws Exception { return Long.parseLong(next()); } public double nextDouble() throws Exception { return Double.parseDouble(next()); } public String next() throws Exception { while (!st.hasMoreTokens()) { st = new StringTokenizer(br.readLine()); } return st.nextToken(); } }