Little boy Gerald studies at school which is quite far from his house. That's why he has to go there by bus every day. The way from home to school is represented by a segment of a straight line; the segment contains exactly n + 1 bus stops. All of them are numbered with integers from 0 to n in the order in which they follow from Gerald's home. The bus stop by Gerald's home has number 0 and the bus stop by the school has number n.

There are m buses running between the house and the school: the i-th bus goes from stop si to ti (si < ti), visiting all the intermediate stops in the order in which they follow on the segment. Besides, Gerald's no idiot and he wouldn't get off the bus until it is still possible to ride on it closer to the school (obviously, getting off would be completely pointless). In other words, Gerald can get on the i-th bus on any stop numbered from si to ti - 1 inclusive, but he can get off the i-th bus only on the bus stop ti.

Gerald can't walk between the bus stops and he also can't move in the direction from the school to the house.

Gerald wants to know how many ways he has to get from home to school. Tell him this number. Two ways are considered different if Gerald crosses some segment between the stops on different buses. As the number of ways can be too much, find the remainder of a division of this number by 1000000007 (109 + 7).

Input

The first line contains two space-separated integers: n and m (1 ≤ n ≤ 109, 0 ≤ m ≤ 105). Then follow m lines each containing two integers si, ti. They are the numbers of starting stops and end stops of the buses (0 ≤ si < ti ≤ n).

Output

Print the only number — the number of ways to get to the school modulo 1000000007 (109 + 7).

Examples

Input

2 2
0 1
1 2


Output

1


Input

3 2
0 1
1 2


Output

0


Input

5 5
0 1
0 2
0 3
0 4
0 5


Output

16

Note

The first test has the only variant to get to school: first on bus number one to the bus stop number one; then on bus number two to the bus stop number two.

In the second test no bus goes to the third bus stop, where the school is positioned. Thus, the correct answer is 0.

In the third test Gerald can either get or not on any of the first four buses to get closer to the school. Thus, the correct answer is 24 = 16.
import java.io.*;
import java.util.*;
import java.util.stream.IntStream;
import java.util.stream.Stream;

public class Main implements Runnable {
    static final int MOD = (int) 1e9 + 7;
    static final int MI = (int) 1e9;
    static final long ML = (long) 1e18;
    static final Reader in = new Reader();
    static final PrintWriter out = new PrintWriter(System.out);
    StringBuilder answer = new StringBuilder();

    public static void main(String[] args) {
        new Thread(null, new Main(), "persefone", 1 << 32).start();
    }

    @Override
    public void run() {
        solve();
        printf();
        flush();
    }

    void solve() {
        int n = in.nextInt();
        int m = in.nextInt();
        Route[] routes = new Route[m + 1];
        for (int i = 1; i <= m; i++) {
            routes[i] = new Route(in.nextInt(), in.nextInt());
        }
        Arrays.sort(routes, 1, m + 1);
        Map<Integer, Integer> map = new HashMap<>();
        Fenwick fen = new Fenwick(m);
        long ans = 0;
        for (int i = 1; i <= m; i++) {
            int can = map.getOrDefault(routes[i].to, i) - 1;
            if (can == i - 1) map.put(routes[i].to, i);
            int pos = Utils.lowerBound(routes, 1, i, routes[i].from);
            long cur = fen.sum(pos, can);
            if (routes[i].from == 0) cur++;
            fen.update(i, cur);
            if (routes[i].to == n) {
                ans = (ans + cur) % MOD;
            }
        }
        printf(ans);
    }

    static class Utils {
        static int lowerBound(Route[] routes, int l, int r, int k) {
            int m = 0, ans = r;
            while (l < r) if (routes[m = l + r >> 1].to >= k) ans = r = m;
            else l = m + 1;
            return ans;
        }
    }

    static class Route implements Comparable<Route> {
        private int from, to;

        public Route(int from, int to) {
            this.from = from;
            this.to = to;
        }

        @Override
        public int compareTo(Route that) {
            return this.to - that.to;
        }

        @Override
        public String toString() {
            return "Route{" +
                    "from=" + from +
                    ", to=" + to +
                    '}';
        }
    }

    static class Fenwick {
        private int n;
        private long[] sum;

        public Fenwick(int n) {
            this.n = n + 10;
            this.sum = new long[n + 10];
        }

        public void update(int i, long v) {
            for (; i < n; i += i & -i) {
                sum[i] = (sum[i] + v) % MOD;
            }
        }

        long sum(int i) {
            long res = 0;
            for (; i > 0; i -= i & -i) {
                res = (res + sum[i]) % MOD;
            }
            return res;
        }

        long sum(int i, int j) {
            if (i > j) return 0;
            return (sum(j) - sum(i - 1) + MOD) % MOD;
        }
    }

    static class SegmentTreeMax {
        private int n;
        private int[] max;

        public SegmentTreeMax(int n) {
            this.n = n;
            this.max = new int[4 * n + 4];
            Arrays.fill(max, -1);
        }

        int calc(int x, int y) {
            return Math.max(x, y);
        }

        public void update(int currentVertex, int currentLeft, int currentRight, int pos, int value) {
            if (currentLeft == currentRight) max[currentVertex] = value;
            else {
                int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
                if (pos <= mid)
                    update(doubleVex, currentLeft, mid, pos, value);
                else
                    update(doubleVex + 1, mid + 1, currentRight, pos, value);
                max[currentVertex] = calc(max[doubleVex], max[doubleVex + 1]);
            }
        }

        public void update(int pos, int value) {
            update(1, 0, n - 1, pos, value);
        }

        public int getFirst(int currentVertex, int currentLeft, int currentRight, int left, int right, int k) {
            if (currentLeft > right || currentRight < left || max[currentVertex] <= k) return -1;
            if (currentLeft == currentRight) return currentLeft;
            int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
            int ans = getFirst(doubleVex, currentLeft, mid, left, right, k);
            if (ans >= 0) {
                return ans;
            }
            return getFirst(doubleVex + 1, mid + 1, currentRight, left, right, k);
        }

        public int getFirst(int left, int right, int k) {
            return getFirst(1, 0, n - 1, left, right, k);
        }
    }


    static class SegmentTreeSum {
        private int n;
        private int[] a, sum;

        public SegmentTreeSum(int[] a, int n) {
            this.n = n;
            this.a = a;
            this.sum = new int[4 * n + 4];
            build(1, 0, n - 1);
        }

        public void build(int currentVertex, int currentLeft, int currentRight) {
            if (currentLeft == currentRight) sum[currentVertex] = a[currentLeft];
            else {
                int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
                build(doubleVex, currentLeft, mid);
                build(doubleVex + 1, mid + 1, currentRight);
                sum[currentVertex] = sum[doubleVex] + sum[doubleVex + 1];
            }
        }

        public void update(int currentVertex, int currentLeft, int currentRight, int pos, int value) {
            if (currentLeft == currentRight) sum[currentVertex] = a[pos] = value;
            else {
                int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
                if (pos <= mid)
                    update(doubleVex, currentLeft, mid, pos, value);
                else
                    update(doubleVex + 1, mid + 1, currentRight, pos, value);
                sum[currentVertex] = sum[doubleVex] + sum[doubleVex + 1];
            }
        }

        public void update(int pos, int value) {
            update(1, 0, n - 1, pos, value);
        }

        public int sum(int currentVertex, int currentLeft, int currentRight, int left, int right) {
            if (currentLeft > right || currentRight < left) return 0;
            else if (left <= currentLeft && currentRight <= right) return sum[currentVertex];
            int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
            return sum(doubleVex, currentLeft, mid, left, right) + sum(doubleVex + 1, mid + 1, currentRight, left, right);
        }

        public int sum(int left, int right) {
            return sum(1, 0, n - 1, left, right);
        }

        public int kth(int currentVertex, int currentLeft, int currentRight, int k) {
            if (k > sum[currentVertex]) return -1;
            if (currentLeft == currentRight) return currentLeft;
            int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
            if (k <= sum[doubleVex])
                return kth(doubleVex, currentLeft, mid, k);
            else
                return kth(doubleVex + 1, mid + 1, currentRight, k - sum[doubleVex]);
        }

        public int kth(int k) {
            return kth(1, 0, n - 1, k);
        }
    }


    static class TreeSetTree {
        private int n;
        private int[] a;
        private NavigableSet<Integer>[] set;

        public TreeSetTree(int[] a, int n) {
            this.n = n;
            this.a = a;
            this.set = Stream.generate(TreeSet::new).limit(4 * n + 4).toArray(NavigableSet[]::new);
            build(1, 0, n - 1);
        }

        void merge(NavigableSet<Integer> z, NavigableSet<Integer> x, NavigableSet<Integer> y) {
            z.addAll(x);
            z.addAll(y);
        }

        public void build(int currentVertex, int currentLeft, int currentRight) {
            if (currentLeft == currentRight) set[currentVertex].add(a[currentLeft]);
            else {
                int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
                build(doubleVex, currentLeft, mid);
                build(doubleVex + 1, mid + 1, currentRight);
                merge(set[currentVertex], set[doubleVex], set[doubleVex + 1]);
            }
        }

        public void update(int currentVertex, int currentLeft, int currentRight, int pos, int value) {
            set[currentVertex].remove(a[pos]);
            set[currentVertex].add(value);
            if (currentLeft == currentRight) {
                a[pos] = value;
            } else {
                int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
                if (pos <= mid)
                    update(doubleVex, currentLeft, mid, pos, value);
                else
                    update(doubleVex + 1, mid + 1, currentRight, pos, value);
            }
        }

        public void update(int pos, int value) {
            update(1, 0, n - 1, pos, value);
        }

        public int get(int currentVertex, int currentLeft, int currentRight, int left, int right, int k) {
            if (currentLeft > right || currentRight < left) return 0;
            else if (left <= currentLeft && currentRight <= right) {
                Integer floor = set[currentVertex].floor(k);
                return floor == null ? 0 : floor;
            }
            int mid = currentLeft + currentRight >> 1, doubleVex = currentVertex << 1;
            return Math.max(get(doubleVex, currentLeft, mid, left, right, k),
                    get(doubleVex + 1, mid + 1, currentRight, left, right, k));
        }

        public int get(int left, int right, int k) {
            return get(1, 0, n - 1, left, right, k);
        }
    }

    static class ListUtils {
        static int lowerBound(List<Integer> list, int l, int r, int k) {
            int m = 0, ans = r;
            while (l < r) if (list.get(m = l + r >> 1) >= k) ans = r = m;
            else l = m + 1;
            return ans;
        }

        static int upperBound(List<Integer> list, int l, int r, int k) {
            int m = 0, ans = r;
            while (l < r) if (list.get(m = l + r >> 1) > k) ans = r = m;
            else l = m + 1;
            return ans;
        }

        static int amountOfNumbersEqualTo(List<Integer> list, int l, int r, int k) {
            return upperBound(list, l, r, k) - lowerBound(list, l, r, k);
        }

        static int amountOfNumbersEqualTo(List<Integer> list, int k) {
            return upperBound(list, 0, list.size(), k) - lowerBound(list, 0, list.size(), k);
        }


    }

    static class ArrayUtils {
        static int lowerBound(int[] a, int l, int r, int k) {
            int m = 0, ans = r;
            while (l < r) if (a[m = l + r >> 1] >= k) ans = r = m;
            else l = m + 1;
            return ans;
        }

        static int upperBound(int[] a, int l, int r, int k) {
            int m = 0, ans = r;
            while (l < r) if (a[m = l + r >> 1] > k) ans = r = m;
            else l = m + 1;
            return ans;
        }

        static int lowerBound(int[] a, int k) {
            return lowerBound(a, 0, a.length, k);
        }

        static int upperBound(int[] a, int k) {
            return upperBound(a, 0, a.length, k);
        }

        static void compressed(int[] a, int n) {
            int[] b = a.clone();
            Arrays.sort(b);
            for (int i = 0; i < n; i++) {
                a[i] = lowerBound(b, a[i]) + 1;
            }
        }

        static void compressed(int[] a, int l, int r) {
            if (l >= r) return;
            int[] b = new int[r - l];
            System.arraycopy(a, l, b, 0, r - l);
            Arrays.sort(b);
            for (int i = l; i < r; i++) a[i] = lowerBound(b, a[i]) + 1;
        }
    }

    static class IntegerUtils {
        // returns { gcd(a,b), x, y } such that gcd(a,b) = a*x + b*y
        static long[] euclid(long a, long b) {
            long x = 1, y = 0, x1 = 0, y1 = 1, t;
            while (b != 0) {
                long q = a / b;
                t = x;
                x = x1;
                x1 = t - q * x1;
                t = y;
                y = y1;
                y1 = t - q * y1;
                t = b;
                b = a - q * b;
                a = t;
            }
            return a > 0 ? new long[]{a, x, y} : new long[]{-a, -x, -y};
        }

        static int[] generatePrimesUpTo(int n) {
            boolean[] composite = new boolean[n + 1];
            for (int i = 2; i <= n; i++) {
                for (int j = i; 1l * i * j <= n; j++) {
                    composite[i * j] = true;
                }
            }
            return IntStream.rangeClosed(2, n).filter(i -> !composite[i]).toArray();
        }

        static int[] smallestFactor(int n) {
            int[] sf = new int[n + 1];
            for (int i = 2; i <= n; i++) {
                if (sf[i] == 0) {
                    sf[i] = i;
                    for (int j = i; 1l * i * j <= n; j++) {
                        if (sf[i * j] == 0) {
                            sf[i * j] = i;
                        }
                    }
                }
            }
            return sf;
        }

        static int phi(int n) {
            int result = n;
            for (int i = 2; 1l * i * i <= n; i++) {
                if (n % i == 0) {
                    while (n % i == 0) n /= i;
                    result -= result / i;
                }
            }
            if (n > 1) result -= result / n;
            return result;
        }

        static long phi(long n) {
            // n <= 10 ^ 12;
            long result = n;
            for (int i = 2; 1l * i * i <= n; i++) {
                if (n % i == 0) {
                    while (n % i == 0) n /= i;
                    result -= result / i;
                }
            }
            if (n > 1) result -= result / n;
            return result;
        }

        static long[] n_thFiboNaCi(long n, int p) {
            // f[n + k] = f[n + 1].f[k] + f[n].f[k - 1]
            if (n == 0) return new long[]{0, 1};
            long[] a = n_thFiboNaCi(n >> 1, p);
            long c = (2 * a[1] - a[0] + p) % p * a[0] % p;
            long d = (a[1] * a[1] % p + a[0] * a[0] % p) % p;
            if (n % 2 == 0) return new long[]{c, d};
            else return new long[]{d, (c + d) % p};
        }

        static long modPow(int base, int exponential, int p) {
            if (exponential == 0) return 1;
            long x = modPow(base, exponential >> 1, p) % p;
            return exponential % 2 == 0 ? x * x % p : x * x % p * base % p;
        }

        static long modPow(long base, int exponential, int p) {
            if (exponential == 0) return 1;
            long x = modPow(base, exponential >> 1, p) % p;
            return exponential % 2 == 0 ? x * x % p : x * x % p * base % p;
        }

        static long modPow(long base, long exponential, int p) {
            if (exponential == 0) return 1;
            long x = modPow(base, exponential >> 1, p) % p;
            return exponential % 2 == 0 ? x * x % p : x * x % p * base % p;
        }

        static long[] generateFactorialArray(int n, int p) {
            long[] factorial = new long[n + 1];
            factorial[0] = 1;
            for (int i = 1; i <= n; i++) factorial[i] = (factorial[i - 1] * i) % p;
            return factorial;
        }

        static long cNkModP(long[] factorial, int n, int k, int p) {
            return factorial[n] * modPow(factorial[k], p - 2, p) % p * modPow(factorial[n - k], p - 2, p) % p;
        }

        static long gcd(long a, long b) {
            return b == 0 ? a : gcd(b, a % b);
        }

        static int gcd(int a, int b) {
            return b == 0 ? a : gcd(b, a % b);
        }

    }

    static class SparseTableMax {
        private int n, blocks;
        private int[] log, data;
        private int[][] max;

        public SparseTableMax(int[] data, int n) {
            this.n = n;
            this.data = data;
            this.log = new int[n + 1];
            for (int i = 2; i <= n; i++) {
                log[i] = log[i >> 1] + 1;
            }
            this.blocks = log[n];
            this.max = new int[n][blocks + 1];
            for (int i = 0; i < n; i++) {
                max[i][0] = data[i];
            }
            build();
        }

        int calc(int a, int b) {
            return Math.max(a, b);
        }

        void build() {
            for (int j = 1; j <= blocks; j++) {
                for (int i = 0; i + (1 << j) <= n; i++) {
                    max[i][j] = calc(max[i][j - 1], max[i + (1 << j - 1)][j - 1]);
                }
            }
        }

        int getMax(int l, int r) {
            int k = log[r - l + 1];
            return calc(max[l][k], max[r - (1 << k) + 1][k]);
        }
    }

    static class DSU {
        protected int vertex, countCC;
        protected int[] id, size;

        public DSU(int vertex) {
            this.vertex = vertex;
            this.id = IntStream.range(0, vertex).toArray();
            this.size = new int[vertex];
            Arrays.fill(size, 1);
            countCC = vertex;
        }

        int find(int i) {
            return id[i] == i ? i : (id[i] = find(id[i]));
        }

        void unite(int i, int j) {
            int x = find(i);
            int y = find(j);
            if (x == y) return;
            countCC--;
            if (size[x] > size[y]) {
                id[y] = id[x];
                size[x] += size[y];
                size[y] = 0;
                return;
            }
            id[x] = id[y];
            size[y] += size[x];
            size[x] = 0;
        }

        boolean isConnected(int i, int j) {
            return find(i) == find(j);
        }

        int connectedComponents() {
            return countCC;
        }
    }


    void printf() {
        out.print(answer);
    }

    void close() {
        out.close();
    }

    void flush() {
        out.flush();
    }

    void printf(Stream<?> str) {
        str.forEach(o -> add(o, " "));
        add("\n");
    }


    void printf(Object... obj) {
        printf(false, obj);
    }

    void printfWithDescription(Object... obj) {
        printf(true, obj);
    }


    private void printf(boolean b, Object... obj) {

        if (obj.length > 1) {
            for (int i = 0; i < obj.length; i++) {
                if (b) add(obj[i].getClass().getSimpleName(), " - ");
                if (obj[i] instanceof Collection<?>) {
                    printf((Collection<?>) obj[i]);
                } else if (obj[i] instanceof int[][]) {
                    printf((int[][]) obj[i]);
                } else if (obj[i] instanceof long[][]) {
                    printf((long[][]) obj[i]);
                } else if (obj[i] instanceof double[][]) {
                    printf((double[][]) obj[i]);
                } else printf(obj[i]);
            }
            return;
        }

        if (b) add(obj[0].getClass().getSimpleName(), " - ");
        printf(obj[0]);
    }

    void printf(Object o) {
        if (o instanceof int[])
            printf(Arrays.stream((int[]) o).boxed());
        else if (o instanceof char[])
            printf(new String((char[]) o));
        else if (o instanceof long[])
            printf(Arrays.stream((long[]) o).boxed());
        else if (o instanceof double[])
            printf(Arrays.stream((double[]) o).boxed());
        else if (o instanceof boolean[]) {
            for (boolean b : (boolean[]) o) add(b, " ");
            add("\n");
        } else
            add(o, "\n");
    }

    void printf(int[]... obj) {
        for (int i = 0; i < obj.length; i++) printf(obj[i]);
    }

    void printf(long[]... obj) {
        for (int i = 0; i < obj.length; i++) printf(obj[i]);
    }

    void printf(double[]... obj) {
        for (int i = 0; i < obj.length; i++) printf(obj[i]);
    }

    void printf(boolean[]... obj) {
        for (int i = 0; i < obj.length; i++) printf(obj[i]);
    }

    void printf(Collection<?> col) {
        printf(col.stream());
    }

    <T, K> void add(T t, K k) {
        if (t instanceof Collection<?>) {
            ((Collection<?>) t).forEach(i -> add(i, " "));
        } else if (t instanceof Object[]) {
            Arrays.stream((Object[]) t).forEach(i -> add(i, " "));
        } else
            add(t);
        add(k);
    }


    <T> void add(T t) {
        answer.append(t);
    }

    @SuppressWarnings("unchecked")
    <T extends Comparable<? super T>> T min(T... t) {
        if (t.length == 0)
            return null;
        T m = t[0];
        for (int i = 1; i < t.length; i++)
            if (t[i].compareTo(m) < 0)
                m = t[i];
        return m;
    }

    @SuppressWarnings("unchecked")
    <T extends Comparable<? super T>> T max(T... t) {
        if (t.length == 0)
            return null;
        T m = t[0];
        for (int i = 1; i < t.length; i++)
            if (t[i].compareTo(m) > 0)
                m = t[i];
        return m;
    }

    static class Pair<K extends Comparable<? super K>, V extends Comparable<? super V>>
            implements Comparable<Pair<K, V>> {
        private K k;
        private V v;

        Pair(K k, V v) {
            this.k = k;
            this.v = v;
        }

        @SuppressWarnings("unchecked")
        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || !(o instanceof Pair)) return false;
            Pair<K, V> p = (Pair<K, V>) o;
            return k.compareTo(p.k) == 0 && v.compareTo(p.v) == 0;
        }

        @Override
        public int hashCode() {
            int hash = 31;
            hash = hash * 89 + k.hashCode();
            hash = hash * 89 + v.hashCode();
            return hash;
        }

        @Override
        public int compareTo(Pair<K, V> pair) {
            return k.compareTo(pair.k) == 0 ? v.compareTo(pair.v) : k.compareTo(pair.k);
        }

        @Override
        public Pair<K, V> clone() {
            return new Pair<K, V>(this.k, this.v);
        }

        @Override
        public String toString() {
            return String.valueOf(k).concat(" ").concat(String.valueOf(v)).concat("\n");
        }
    }

    static class Reader {
        private BufferedReader br;
        private StringTokenizer st;

        Reader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        Reader(String fileName) throws FileNotFoundException {
            br = new BufferedReader(new FileReader(fileName));
        }

        boolean isReady() throws IOException {
            return br.ready();
        }

        String next() {
            try {
                while (st == null || !st.hasMoreTokens()) {
                    st = new StringTokenizer(br.readLine());
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        int[] nextIntArray(int n) {
            int[] arr = new int[n];
            for (int i = 0; i < n; i++)
                arr[i] = nextInt();
            return arr;
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        String nextLine() {
            String s = "";
            try {
                s = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return s;
        }
    }
}