description: A group of n alpinists has just reached the foot of the mountain. The initial difficulty of climbing this mountain can be described as an integer d.
  
  Each alpinist can be described by two integers s and a, where s is his skill of climbing mountains and a is his neatness.
  
  An alpinist of skill level s is able to climb a mountain of difficulty p only if p ≤ s. As an alpinist climbs a mountain, they affect the path and thus may change mountain difficulty. Specifically, if an alpinist of neatness a climbs a mountain of difficulty p the difficulty of this mountain becomes max(p, a). 
  
  Alpinists will climb the mountain one by one. And before the start, they wonder, what is the maximum number of alpinists who will be able to climb the mountain if they choose the right order. As you are the only person in the group who does programming, you are to answer the question.
  
  Note that after the order is chosen, each alpinist who can climb the mountain, must climb the mountain at that time. 
  
  Input
  
  The first line contains two integers n and d (1 ≤ n ≤ 500 000; 0 ≤ d ≤ 10^9) — the number of alpinists and the initial difficulty of the mountain.
  
  Each of the next n lines contains two integers s_i and a_i (0 ≤ s_i, a_i ≤ 10^9) that define the skill of climbing and the neatness of the i-th alpinist.
  
  Output
  
  Print one integer equal to the maximum number of alpinists who can climb the mountain if they choose the right order to do so.
  
  Examples
  
  Input
  
  
  3 2
  2 6
  3 5
  5 7
  
  
  Output
  
  
  2
  
  
  Input
  
  
  3 3
  2 4
  6 4
  4 6
  
  
  Output
  
  
  2
  
  
  Input
  
  
  5 0
  1 5
  4 8
  2 7
  7 6
  3 2
  
  
  Output
  
  
  3
  
  Note
  
  In the first example, alpinists 2 and 3 can climb the mountain if they go in this order. There is no other way to achieve the answer of 2.
  
  In the second example, alpinist 1 is not able to climb because of the initial difficulty of the mountain, while alpinists 2 and 3 can go up in any order.
  
  In the third example, the mountain can be climbed by alpinists 5, 3 and 4 in this particular order. There is no other way to achieve optimal answer.
solution: //package round751;
  import java.io.*;
  import java.util.*;
  
  public class D {
  	InputStream is;
  	FastWriter out;
  	String INPUT = "";
  	
  	void solve()
  	{
  		int n = ni(), D = ni();
  		int[] xs = new int[2*n+1];
  		for(int i = 0;i < 2*n;i++){
  			xs[i] = ni();
  		}
  		xs[2*n] = D;
  		xs = shrink(xs);
  		D = xs[2*n];
  		int[][] fd = new int[n][];
  		int[][] rv = new int[n][];
  		int pf = 0, pr = 0;
  		for(int i = 0;i < n;i++){
  			if(xs[2*i] < D)continue;
  			if(xs[2*i] <= xs[2*i+1]){
  				fd[pf++] = new int[]{xs[2*i], xs[2*i+1]};
  			}else{
  				rv[pr++] = new int[]{xs[2*i], xs[2*i+1]};
  			}
  		}
  		fd = Arrays.copyOf(fd, pf);
  		Arrays.sort(fd, (x, y) -> {
  			if(x[0] != y[0])return x[0] - y[0];
  			return x[1] - y[1];
  		});
  		rv = Arrays.copyOf(rv, pr);
  		int[] inr = new int[pf];
  		int[][] ef = new int[2*pf][];
  		int p = 0;
  		for(int i = 0;i < pf;i++){
  			ef[p++] = new int[]{fd[i][0], i, -1};
  			ef[p++] = new int[]{fd[i][1], i, 1};
  		}
  		Arrays.sort(ef, Comparator.comparingInt(x -> x[0]));
  		Arrays.sort(rv, Comparator.comparingInt(x -> x[1]));
  		int[] ft = new int[2*n+5];
  
  		int q = 0;
  		for(int[] e : ef){
  			while(q < pr && rv[q][1] <= e[0]){
  				addFenwick(ft, rv[q][0], 1);
  				q++;
  			}
  			inr[e[1]] += e[2] * (sumFenwick(ft, 2*n) - sumFenwick(ft, fd[e[1]][1]-1));
  //			tr(e, sumFenwick(ft, 2*n) - sumFenwick(ft, fd[e[1]][1]-1));
  		}
  //		tr("ef", ef);
  //		tr(inr);
  
  		int[] bef = new int[2*n+5];
  		for(int[] u : rv){
  			bef[u[1]]++;
  		}
  		for(int i = 1;i <= 2*n;i++){
  			bef[i] += bef[i-1];
  		}
  //		tr(bef);
  
  		long ans = pr;
  
  //		tr(fd, rv);
  		long[] anss = new long[pf];
  		SegmentTreeRMQ st = new SegmentTreeRMQ(2*n+1);
  		for(int i = 0;i < pf;i++){
  //			tr(fd[i], Math.max(0, -st.min(0, fd[i][0]+1)), bef[fd[i][0]], inr[i]);
  			anss[i] = Math.max(0, -st.min(0, fd[i][0]+1)) + 1 + bef[fd[i][0]] + inr[i];
  			ans = Math.max(ans, anss[i] + pr - bef[fd[i][1]]);
  			st.update(fd[i][1], (int)-(anss[i] - bef[fd[i][1]]));
  		}
  //		tr(anss);
  		out.println(ans);
  	}
  
  	public static class SegmentTreeRMQ {
  		public final int M, H, N;
  		public int[] vals;
  		public static final int I = Integer.MAX_VALUE;
  
  		public SegmentTreeRMQ(int n)
  		{
  			N = n;
  			M = Integer.highestOneBit(Math.max(N-1, 1))<<2;
  			H = M>>>1;
  			vals = new int[M];
  			Arrays.fill(vals, 0, M, I);
  		}
  
  		public SegmentTreeRMQ(int[] a)
  		{
  			this(a.length);
  			for(int i = 0;i < N;i++){
  				vals[H+i] = a[i];
  			}
  			//		Arrays.fill(vals, H+N, M, I);
  			for(int i = H-1;i >= 1;i--)propagate(i);
  		}
  
  		public void update(int pos, int x)
  		{
  			vals[H+pos] = Math.min(vals[H+pos], x);
  			for(int i = (H+pos)>>>1;i >= 1;i >>>= 1)propagate(i);
  		}
  
  		private void propagate(int i)
  		{
  			vals[i] = Math.min(vals[2*i], vals[2*i+1]);
  		}
  
  		public int min(int l, int r){
  			int min = I;
  			if(l >= r)return min;
  			l += H; r += H;
  			for(;l < r;l>>>=1,r>>>=1){
  				if((l&1) == 1)min = Math.min(min, vals[l++]);
  				if((r&1) == 1)min = Math.min(min, vals[--r]);
  			}
  			return min;
  		}
  
  		public int firstle(int l, int v) {
  			if(l >= H)return -1;
  			int cur = H+l;
  			while(true){
  				if(vals[cur] <= v){
  					if(cur >= H)return cur-H;
  					cur = 2*cur;
  				}else{
  					cur++;
  					if((cur&cur-1) == 0)return -1;
  					if((cur&1)==0)cur>>>=1;
  				}
  			}
  		}
  
  		public int lastle(int l, int v) {
  			if(l < 0)return -1;
  			int cur = H+l;
  			while(true){
  				if(vals[cur] <= v){
  					if(cur >= H)return cur-H;
  					cur = 2*cur + 1;
  				}else{
  					if((cur&cur-1) == 0)return -1;
  					cur--;
  					if((cur&1)==1)cur>>>=1;
  				}
  			}
  		}
  	}
  
  
  	public static int sumFenwick(int[] ft, int i)
  	{
  		int sum = 0;
  		for(i++;i > 0;i -= i&-i)sum += ft[i];
  		return sum;
  	}
  
  	public static void addFenwick(int[] ft, int l, int r, int v)
  	{
  		addFenwick(ft, l, v);
  		addFenwick(ft, r, -v);
  	}
  
  	public static void addFenwick(int[] ft, int i, int v)
  	{
  		if(v == 0 || i < 0)return;
  		int n = ft.length;
  		for(i++;i < n;i += i&-i)ft[i] += v;
  	}
  
  
  	public static int[] shrink(int[] a) {
  		int n = a.length;
  		int[] b = Arrays.copyOf(a, n);
  		b = radixSort2(b);
  		int p = 1;
  		for(int i = 1;i < n;i++){
  			if(b[i] != b[i-1]){
  				b[p++] = b[i];
  			}
  		}
  		for (int i = 0; i < n; i++) {
  			a[i] = Arrays.binarySearch(b, 0, p, a[i]);
  		}
  		return a;
  	}
  
  	public static int[] radixSort2(int[] a)
  	{
  		int n = a.length;
  		int[] c0 = new int[0x101];
  		int[] c1 = new int[0x101];
  		int[] c2 = new int[0x101];
  		int[] c3 = new int[0x101];
  		for(int v : a) {
  			c0[(v&0xff)+1]++;
  			c1[(v>>>8&0xff)+1]++;
  			c2[(v>>>16&0xff)+1]++;
  			c3[(v>>>24^0x80)+1]++;
  		}
  		for(int i = 0;i < 0xff;i++) {
  			c0[i+1] += c0[i];
  			c1[i+1] += c1[i];
  			c2[i+1] += c2[i];
  			c3[i+1] += c3[i];
  		}
  		int[] t = new int[n];
  		for(int v : a)t[c0[v&0xff]++] = v;
  		for(int v : t)a[c1[v>>>8&0xff]++] = v;
  		for(int v : a)t[c2[v>>>16&0xff]++] = v;
  		for(int v : t)a[c3[v>>>24^0x80]++] = v;
  		return a;
  	}
  
  
  
  	void run() throws Exception
  	{
  		is = oj ? System.in : new ByteArrayInputStream(INPUT.getBytes());
  		out = new FastWriter(System.out);
  		
  		long s = System.currentTimeMillis();
  		solve();
  		out.flush();
  		tr(System.currentTimeMillis()-s+"ms");
  	}
  	
  	public static void main(String[] args) throws Exception { new D().run(); }
  	
  	private byte[] inbuf = new byte[1024];
  	public int lenbuf = 0, ptrbuf = 0;
  	
  	private int readByte()
  	{
  		if(lenbuf == -1)throw new InputMismatchException();
  		if(ptrbuf >= lenbuf){
  			ptrbuf = 0;
  			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
  			if(lenbuf <= 0)return -1;
  		}
  		return inbuf[ptrbuf++];
  	}
  	
  	private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
  	private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }
  	
  	private double nd() { return Double.parseDouble(ns()); }
  	private char nc() { return (char)skip(); }
  	
  	private String ns()
  	{
  		int b = skip();
  		StringBuilder sb = new StringBuilder();
  		while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ')
  			sb.appendCodePoint(b);
  			b = readByte();
  		}
  		return sb.toString();
  	}
  	
  	private char[] ns(int n)
  	{
  		char[] buf = new char[n];
  		int b = skip(), p = 0;
  		while(p < n && !(isSpaceChar(b))){
  			buf[p++] = (char)b;
  			b = readByte();
  		}
  		return n == p ? buf : Arrays.copyOf(buf, p);
  	}
  
  	private int[] na(int n)
  	{
  		int[] a = new int[n];
  		for(int i = 0;i < n;i++)a[i] = ni();
  		return a;
  	}
  
  	private long[] nal(int n)
  	{
  		long[] a = new long[n];
  		for(int i = 0;i < n;i++)a[i] = nl();
  		return a;
  	}
  
  	private char[][] nm(int n, int m) {
  		char[][] map = new char[n][];
  		for(int i = 0;i < n;i++)map[i] = ns(m);
  		return map;
  	}
  
  	private int[][] nmi(int n, int m) {
  		int[][] map = new int[n][];
  		for(int i = 0;i < n;i++)map[i] = na(m);
  		return map;
  	}
  
  	private int ni() { return (int)nl(); }
  
  	private long nl()
  	{
  		long num = 0;
  		int b;
  		boolean minus = false;
  		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
  		if(b == '-'){
  			minus = true;
  			b = readByte();
  		}
  
  		while(true){
  			if(b >= '0' && b <= '9'){
  				num = num * 10 + (b - '0');
  			}else{
  				return minus ? -num : num;
  			}
  			b = readByte();
  		}
  	}
  
  	public static class FastWriter
  	{
  		private static final int BUF_SIZE = 1<<13;
  		private final byte[] buf = new byte[BUF_SIZE];
  		private final OutputStream out;
  		private int ptr = 0;
  
  		private FastWriter(){out = null;}
  
  		public FastWriter(OutputStream os)
  		{
  			this.out = os;
  		}
  
  		public FastWriter(String path)
  		{
  			try {
  				this.out = new FileOutputStream(path);
  			} catch (FileNotFoundException e) {
  				throw new RuntimeException("FastWriter");
  			}
  		}
  
  		public FastWriter write(byte b)
  		{
  			buf[ptr++] = b;
  			if(ptr == BUF_SIZE)innerflush();
  			return this;
  		}
  
  		public FastWriter write(char c)
  		{
  			return write((byte)c);
  		}
  
  		public FastWriter write(char[] s)
  		{
  			for(char c : s){
  				buf[ptr++] = (byte)c;
  				if(ptr == BUF_SIZE)innerflush();
  			}
  			return this;
  		}
  
  		public FastWriter write(String s)
  		{
  			s.chars().forEach(c -> {
  				buf[ptr++] = (byte)c;
  				if(ptr == BUF_SIZE)innerflush();
  			});
  			return this;
  		}
  
  		private static int countDigits(int l) {
  			if (l >= 1000000000) return 10;
  			if (l >= 100000000) return 9;
  			if (l >= 10000000) return 8;
  			if (l >= 1000000) return 7;
  			if (l >= 100000) return 6;
  			if (l >= 10000) return 5;
  			if (l >= 1000) return 4;
  			if (l >= 100) return 3;
  			if (l >= 10) return 2;
  			return 1;
  		}
  
  		public FastWriter write(int x)
  		{
  			if(x == Integer.MIN_VALUE){
  				return write((long)x);
  			}
  			if(ptr + 12 >= BUF_SIZE)innerflush();
  			if(x < 0){
  				write((byte)'-');
  				x = -x;
  			}
  			int d = countDigits(x);
  			for(int i = ptr + d - 1;i >= ptr;i--){
  				buf[i] = (byte)('0'+x%10);
  				x /= 10;
  			}
  			ptr += d;
  			return this;
  		}
  
  		private static int countDigits(long l) {
  			if (l >= 1000000000000000000L) return 19;
  			if (l >= 100000000000000000L) return 18;
  			if (l >= 10000000000000000L) return 17;
  			if (l >= 1000000000000000L) return 16;
  			if (l >= 100000000000000L) return 15;
  			if (l >= 10000000000000L) return 14;
  			if (l >= 1000000000000L) return 13;
  			if (l >= 100000000000L) return 12;
  			if (l >= 10000000000L) return 11;
  			if (l >= 1000000000L) return 10;
  			if (l >= 100000000L) return 9;
  			if (l >= 10000000L) return 8;
  			if (l >= 1000000L) return 7;
  			if (l >= 100000L) return 6;
  			if (l >= 10000L) return 5;
  			if (l >= 1000L) return 4;
  			if (l >= 100L) return 3;
  			if (l >= 10L) return 2;
  			return 1;
  		}
  
  		public FastWriter write(long x)
  		{
  			if(x == Long.MIN_VALUE){
  				return write("" + x);
  			}
  			if(ptr + 21 >= BUF_SIZE)innerflush();
  			if(x < 0){
  				write((byte)'-');
  				x = -x;
  			}
  			int d = countDigits(x);
  			for(int i = ptr + d - 1;i >= ptr;i--){
  				buf[i] = (byte)('0'+x%10);
  				x /= 10;
  			}
  			ptr += d;
  			return this;
  		}
  
  		public FastWriter write(double x, int precision)
  		{
  			if(x < 0){
  				write('-');
  				x = -x;
  			}
  			x += Math.pow(10, -precision)/2;
  			//		if(x < 0){ x = 0; }
  			write((long)x).write(".");
  			x -= (long)x;
  			for(int i = 0;i < precision;i++){
  				x *= 10;
  				write((char)('0'+(int)x));
  				x -= (int)x;
  			}
  			return this;
  		}
  
  		public FastWriter writeln(char c){
  			return write(c).writeln();
  		}
  
  		public FastWriter writeln(int x){
  			return write(x).writeln();
  		}
  
  		public FastWriter writeln(long x){
  			return write(x).writeln();
  		}
  
  		public FastWriter writeln(double x, int precision){
  			return write(x, precision).writeln();
  		}
  
  		public FastWriter write(int... xs)
  		{
  			boolean first = true;
  			for(int x : xs) {
  				if (!first) write(' ');
  				first = false;
  				write(x);
  			}
  			return this;
  		}
  
  		public FastWriter write(long... xs)
  		{
  			boolean first = true;
  			for(long x : xs) {
  				if (!first) write(' ');
  				first = false;
  				write(x);
  			}
  			return this;
  		}
  
  		public FastWriter writeln()
  		{
  			return write((byte)'\n');
  		}
  
  		public FastWriter writeln(int... xs)
  		{
  			return write(xs).writeln();
  		}
  
  		public FastWriter writeln(long... xs)
  		{
  			return write(xs).writeln();
  		}
  
  		public FastWriter writeln(char[] line)
  		{
  			return write(line).writeln();
  		}
  
  		public FastWriter writeln(char[]... map)
  		{
  			for(char[] line : map)write(line).writeln();
  			return this;
  		}
  
  		public FastWriter writeln(String s)
  		{
  			return write(s).writeln();
  		}
  
  		private void innerflush()
  		{
  			try {
  				out.write(buf, 0, ptr);
  				ptr = 0;
  			} catch (IOException e) {
  				throw new RuntimeException("innerflush");
  			}
  		}
  
  		public void flush()
  		{
  			innerflush();
  			try {
  				out.flush();
  			} catch (IOException e) {
  				throw new RuntimeException("flush");
  			}
  		}
  
  		public FastWriter print(byte b) { return write(b); }
  		public FastWriter print(char c) { return write(c); }
  		public FastWriter print(char[] s) { return write(s); }
  		public FastWriter print(String s) { return write(s); }
  		public FastWriter print(int x) { return write(x); }
  		public FastWriter print(long x) { return write(x); }
  		public FastWriter print(double x, int precision) { return write(x, precision); }
  		public FastWriter println(char c){ return writeln(c); }
  		public FastWriter println(int x){ return writeln(x); }
  		public FastWriter println(long x){ return writeln(x); }
  		public FastWriter println(double x, int precision){ return writeln(x, precision); }
  		public FastWriter print(int... xs) { return write(xs); }
  		public FastWriter print(long... xs) { return write(xs); }
  		public FastWriter println(int... xs) { return writeln(xs); }
  		public FastWriter println(long... xs) { return writeln(xs); }
  		public FastWriter println(char[] line) { return writeln(line); }
  		public FastWriter println(char[]... map) { return writeln(map); }
  		public FastWriter println(String s) { return writeln(s); }
  		public FastWriter println() { return writeln(); }
  	}
  
  	public void trnz(int... o)
  	{
  		for(int i = 0;i < o.length;i++)if(o[i] != 0)System.out.print(i+":"+o[i]+" ");
  		System.out.println();
  	}
  
  	// print ids which are 1
  	public void trt(long... o)
  	{
  		Queue<Integer> stands = new ArrayDeque<>();
  		for(int i = 0;i < o.length;i++){
  			for(long x = o[i];x != 0;x &= x-1)stands.add(i<<6|Long.numberOfTrailingZeros(x));
  		}
  		System.out.println(stands);
  	}
  
  	public void tf(boolean... r)
  	{
  		for(boolean x : r)System.out.print(x?'#':'.');
  		System.out.println();
  	}
  
  	public void tf(boolean[]... b)
  	{
  		for(boolean[] r : b) {
  			for(boolean x : r)System.out.print(x?'#':'.');
  			System.out.println();
  		}
  		System.out.println();
  	}
  
  	public void tf(long[]... b)
  	{
  		if(INPUT.length() != 0) {
  			for (long[] r : b) {
  				for (long x : r) {
  					for (int i = 0; i < 64; i++) {
  						System.out.print(x << ~i < 0 ? '#' : '.');
  					}
  				}
  				System.out.println();
  			}
  			System.out.println();
  		}
  	}
  
  	public void tf(long... b)
  	{
  		if(INPUT.length() != 0) {
  			for (long x : b) {
  				for (int i = 0; i < 64; i++) {
  					System.out.print(x << ~i < 0 ? '#' : '.');
  				}
  			}
  			System.out.println();
  		}
  	}
  
  	private boolean oj = System.getProperty("ONLINE_JUDGE") != null;
  	private void tr(Object... o) { if(!oj)System.out.println(Arrays.deepToString(o)); }
  }
  