import java.io.*;
import java.util.*;

public class army_pk {

	void solve() throws IOException {
		int n = nextInt();
		int m = nextInt();
		int[] a = new int[n];
		for (int i = 0; i < n; i++)
			a[i] = nextInt();
		int cnt = 0;
		for (int i = 0; i < n; i++) {
			cnt += check(a, i);
		}
		for (int i = 0; i <m; i++) {
			if (nextToken().equals("?")) {
				if (cnt == n)
					out.println("YES");
				else
					out.println("NO");
			} else {
				int k = nextInt() - 1;
				int x = nextInt();
				cnt -= (check(a, k - 1) + check(a, k));
				a[k] = x;
				cnt += (check(a, k - 1) + check(a, k));
			}
		}
		
	}

	private int check(int[] a, int i) {
		if (i < 0 || i >= a.length)
			return 0;
		if (i < a.length - 1 && a[i] > a[i + 1])
			return 0;
		return 1;
	}

	BufferedReader br;
	StringTokenizer st;
	PrintWriter out;

	void run() {
		try {
			br = new BufferedReader(new InputStreamReader(System.in));
			out = new PrintWriter(System.out);

			br = new BufferedReader(new FileReader(new File("army.in")));
			out = new PrintWriter("army.out");

			solve();

			out.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	public static void main(String[] args) {
		new army_pk().run();
	}

	String nextToken() throws IOException {
		while ((st == null) || !st.hasMoreTokens())
			st = new StringTokenizer(br.readLine());
		return st.nextToken();
	}

	int nextInt() throws NumberFormatException, IOException {
		return Integer.parseInt(nextToken());
	}

	double nextDouble() throws NumberFormatException, IOException {
		return Double.parseDouble(nextToken());
	}

	long nextLong() throws NumberFormatException, IOException {
		return Long.parseLong(nextToken());
	}
}
