You have n distinct points on a plane, none of them lie on OY axis. Check that there is a point after removal of which the remaining points are located on one side of the OY axis.

Input

The first line contains a single positive integer n (2 ≤ n ≤ 105).

The following n lines contain coordinates of the points. The i-th of these lines contains two single integers xi and yi (|xi|, |yi| ≤ 109, xi ≠ 0). No two points coincide.

Output

Print "Yes" if there is such a point, "No" — otherwise.

You can print every letter in any case (upper or lower).

Examples

Input

3
1 1
-1 -1
2 -1


Output

Yes

Input

4
1 1
2 2
-1 1
-2 2


Output

No

Input

3
1 2
2 1
4 60


Output

Yes

Note

In the first example the second point can be removed.

In the second example there is no suitable for the condition point.

In the third example any point can be removed.
import java.io.*;

public class P900A {
    private static class HpReader {
        private BufferedReader in;

        public HpReader(String dir, String inFile, String outFile) {
            initAndRedirectInOut(dir, inFile, outFile);
        }

        private static int ivl(String val) {
            return Integer.parseInt(val);
        }

        private static long lvl(String val) {
            return Long.parseLong(val);
        }

        private void initAndRedirectInOut(String dir, String inFile, String outFile) {
            if (dir != null) {
                try {
                    String containingDirPath = dir.endsWith(File.separator) ? dir : dir + File.separator;
                    if (isDebug && inFile != null) System.setIn(new FileInputStream(new File(containingDirPath + inFile)));
                    if (isDebug && outFile != null) System.setOut(new PrintStream(new File(containingDirPath + outFile)));
                } catch (FileNotFoundException e) {
                    // Do nothing, stdin & stdout are not redirected
                }
            }
            in = new BufferedReader(new InputStreamReader(System.in));
            out = new PrintWriter(System.out);
        }

        private String nextSingleStr() throws IOException {
            return in.readLine();
        }

        private String[] nextLineStr() throws IOException {
            return nextLineStr(0);
        }

        private String[] nextLineStr(int offset) throws IOException {
            String[] inp = nextSingleStr().split(" ");
            String[] rs = new String[offset + inp.length];
            System.arraycopy(inp, 0, rs, offset, inp.length);
            return rs;
        }

        private int nextSingleInt() throws IOException {
            return ivl(in.readLine());
        }

        private int[] nextLineInt() throws IOException {
            return nextLineInt(0);
        }

        private int[] nextLineInt(int offset) throws IOException {
            String[] inp = nextLineStr();
            int[] rs = new int[offset + inp.length];
            for (int i = 0; i < inp.length; i++) rs[offset + i] = ivl(inp[i]);
            return rs;
        }

        private long nextSingleLong() throws IOException {
            return lvl(in.readLine());
        }

        private long[] nextLineLong() throws IOException {
            return nextLineLong(0);
        }

        private long[] nextLineLong(int offset) throws IOException {
            String[] inp = nextLineStr();
            long[] rs = new long[offset + inp.length];
            for (int i = 0; i < inp.length; i++) rs[offset + i] = lvl(inp[i]);
            return rs;
        }

        private int[][] nextMatInt(int lineCount) throws IOException {
            return nextMatInt(lineCount, 0, 0);
        }

        private int[][] nextMatInt(int lineCount, int rowOffset, int colOffset) throws IOException {
            int[][] rs = new int[rowOffset + lineCount][];
            for (int i = rowOffset; i < rs.length; i++) rs[i] = nextLineInt(colOffset);
            return rs;
        }
    }

    private static class HpHelper {
        private static final String LOCAL_DEBUG_FLAG = "COM_PROG_DEBUG";

        private static boolean isDebug() {
            try {
                return Boolean.parseBoolean(System.getenv(HpHelper.LOCAL_DEBUG_FLAG));
            } catch (Exception e) {
                return false;
            }
        }

        private static String createDelimiter(String delimiter) {
            return delimiter == null ? " " : delimiter;
        }

        private static void println(int[] data, String delimiter) {
            delimiter = createDelimiter(delimiter);
            for (int t : data) out.print(t + delimiter);
            out.println();
        }

        private static void println(long[] data, String delimiter) {
            delimiter = createDelimiter(delimiter);
            for (long t : data) out.print(t + delimiter);
            out.println();
        }

        private static <T> void println(T[] data, String delimiter) {
            delimiter = createDelimiter(delimiter);
            for (T t : data) {
                if (t instanceof int[]) {
                    println((int[]) t, delimiter);
                } else if (t instanceof long[]) {
                    println((long[]) t, delimiter);
                } else if (t instanceof Object[]) {
                    println((Object[]) t, delimiter);
                } else {
                    out.print(t + delimiter);
                }
            }
            out.println();
        }
    }

    private static boolean isDebug = HpHelper.isDebug();
    private static HpReader in = new HpReader("/Users/apple/Work/WorkSpaces/CompetitiveProg/", "in.txt", null);
    private static PrintWriter out;

    public static void main(String[] args) throws IOException {
        int n = in.nextSingleInt();
        int lc = 0, rc = 0;
        for (int i = 0; i < n; i++) {
            int[] inp = in.nextLineInt();
            if (inp[0] < 0) lc++;
            else if (inp[0] > 0) rc++;
        }
        out.print(lc <= 1 || rc <= 1 ? "Yes" : "No");

        out.flush();
    }
}
