Little Chris is very keen on his toy blocks. His teacher, however, wants Chris to solve more problems, so he decided to play a trick on Chris.

There are exactly s blocks in Chris's set, each block has a unique number from 1 to s. Chris's teacher picks a subset of blocks X and keeps it to himself. He will give them back only if Chris can pick such a non-empty subset Y from the remaining blocks, that the equality holds: 

<image> "Are you kidding me?", asks Chris.

For example, consider a case where s = 8 and Chris's teacher took the blocks with numbers 1, 4 and 5. One way for Chris to choose a set is to pick the blocks with numbers 3 and 6, see figure. Then the required sums would be equal: (1 - 1) + (4 - 1) + (5 - 1) = (8 - 3) + (8 - 6) = 7.

<image>

However, now Chris has exactly s = 106 blocks. Given the set X of blocks his teacher chooses, help Chris to find the required set Y!

Input

The first line of input contains a single integer n (1 ≤ n ≤ 5·105), the number of blocks in the set X. The next line contains n distinct space-separated integers x1, x2, ..., xn (1 ≤ xi ≤ 106), the numbers of the blocks in X.

Note: since the size of the input and output could be very large, don't use slow output techniques in your language. For example, do not use input and output streams (cin, cout) in C++.

Output

In the first line of output print a single integer m (1 ≤ m ≤ 106 - n), the number of blocks in the set Y. In the next line output m distinct space-separated integers y1, y2, ..., ym (1 ≤ yi ≤ 106), such that the required equality holds. The sets X and Y should not intersect, i.e. xi ≠ yj for all i, j (1 ≤ i ≤ n; 1 ≤ j ≤ m). It is guaranteed that at least one solution always exists. If there are multiple solutions, output any of them.

Examples

Input

3
1 4 5


Output

2
999993 1000000

Input

1
1


Output

1
1000000 
// package ALLD;

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

public class CF405D {
    static FastReader s;
    static PrintWriter out;
    static String INPUT = "3\n" +
            "\n" +
            "1 4 5\n";

    public static void main(String[] args) {
        long time = System.currentTimeMillis();
        boolean oj = System.getProperty("ONLINE_JUDGE") != null;
        out = new PrintWriter(System.out);
        s = new FastReader(oj);
        int n = s.nextInt();
        boolean[] F = new boolean[1000001];

        Arrays.fill(F, false);
        int k = 0;
//        N = Integer.parseInt(in.readLine());
//        t = new StringTokenizer(in.readLine());
        for (int i = 0; i < n; ++i) {
            int v = s.nextInt();
            F[v] = true;
            if (F[1000001 - v]) k++;
        }

        out.println(n);
        for (int i = 1; i <= 1000000; ++i) {
            if (k > 0 && !F[i] && !F[1000001 - i]) {
                out.print(i + " " + (1000001 - i) + " ");
                k--;
            }
            if (F[i] && !F[1000001 - i]) out.print((1000001 - i) + " ");
        }






        if (!oj) {
            System.out.println(Arrays.deepToString(new Object[]{System.currentTimeMillis() - time + " ms"}));
        }
        out.flush();
    }

    private static class Matrix {

        static long[][] I;
        static long mod = 1000000007;

        public static long[][] exp(long[][] M, long n) {
            if (n <= 0) {
                I = new long[M.length][M.length];
                for (int i = 0; i < M.length; i++) {
                    I[i][i] = 1L;
                }
                return I;
            }
            if (n == 1) return M;
            long[][] res = exp(M, n / 2);
            res = mult(res, res);
            if (n % 2 == 0) return res;
            return mult(res, M);
        }

        public static long[][] mult(long[][] p, long[][] q) {
            long[][] r = new long[p.length][q[0].length];
            for (int i = 0; i < p.length; i++)
                for (int j = 0; j < q[0].length; j++)
                    for (int k = 0; k < q.length; k++) {
                        r[i][j] += p[i][k] * q[k][j];
                        r[i][j] %= mod;
                    }
            return r;
        }
    }

    private static class Maths {
        static ArrayList<Long> printDivisors(long n) {
            // Note that this loop runs till square root
            ArrayList<Long> list = new ArrayList<>();
            for (long i = 1; i <= Math.sqrt(n); i++) {
                if (n % i == 0) {
                    if (n / i == i) {
                        list.add(i);
                    } else {
                        list.add(i);
                        list.add(n / i);
                    }
                }
            }
            return list;
        }


        //    GCD - Using Euclid theorem.
        private static long gcd(long a, long b) {
            if (b == 0) {
                return a;
            }

            return gcd(b, a % b);
        }

        //    Extended euclidean algorithm
//    Used to solve equations of the form ax + by = gcd(a,b)
//    return array [d, a, b] such that d = gcd(p, q), ap + bq = d
        static long[] extendedEuclidean(long p, long q) {
            if (q == 0)
                return new long[]{p, 1, 0};

            long[] vals = extendedEuclidean(q, p % q);
            long d = vals[0];
            long a = vals[2];
            long b = vals[1] - (p / q) * vals[2];
            return new long[]{d, a, b};
        }

        // X ^ y mod p
        static long power(long x, long y, long p) {
            long res = 1;
            x = x % p;

            while (y > 0) {
                if ((y & 1) == 1)
                    res = (res * x) % p;
                y = y >> 1;
                x = (x * x) % p;
            }
            return res;
        }

        // Returns modulo inverse of a
        // with respect to m using extended
        // Euclid Algorithm. Refer below post for details:
        // https://www.geeksforgeeks.org/multiplicative-inverse-under-modulo-m/
        static long inv(long a, long m) {
            long m0 = m, t, q;
            long x0 = 0, x1 = 1;

            if (m == 1)
                return 0;

            // Apply extended Euclid Algorithm
            while (a > 1) {
                q = a / m;
                t = m;
                m = a % m;
                a = t;
                t = x0;
                x0 = x1 - q * x0;
                x1 = t;
            }

            // Make x1 positive
            if (x1 < 0)
                x1 += m0;

            return x1;
        }

        // k is size of num[] and rem[].
        // Returns the smallest number
        // x such that:
        // x % num[0] = rem[0],
        // x % num[1] = rem[1],
        // ..................
        // x % num[k-2] = rem[k-1]
        // Assumption: Numbers in num[] are pairwise
        // coprime (gcd for every pair is 1)
        static long findMinX(long num[], long rem[], long k) {
            int prod = 1;
            for (int i = 0; i < k; i++)
                prod *= num[i];

            int result = 0;
            for (int i = 0; i < k; i++) {
                long pp = prod / num[i];
                result += rem[i] * inv(pp, num[i]) * pp;
            }

            return result % prod;
        }
    }

    private static class BS {
        //  Binary search
        private static int binarySearch(int[] arr, int ele) {
            int low = 0;
            int high = arr.length - 1;
            while (low <= high) {
                int mid = (low + high) / 2;
                if (arr[mid] == ele) {
                    return mid;
                } else if (ele < arr[mid]) {
                    high = mid - 1;
                } else {
                    low = mid + 1;
                }
            }
            return -1;
        }

        //    First occurence using binary search
        private static int binarySearchFirstOccurence(int[] arr, int ele) {
            int low = 0;
            int high = arr.length - 1;
            int ans = -1;
            while (low <= high) {
                int mid = (low + high) / 2;
                if (arr[mid] == ele) {
                    ans = mid;
                    high = mid - 1;
                } else if (ele < arr[mid]) {
                    high = mid - 1;
                } else {
                    low = mid + 1;
                }
            }
            return ans;
        }


        //    Last occurenece using binary search
        private static int binarySearchLastOccurence(int[] arr, int ele) {
            int low = 0;
            int high = arr.length - 1;
            int ans = -1;
            while (low <= high) {
                int mid = (low + high) / 2;
                if (arr[mid] == ele) {
                    ans = mid;
                    low = mid + 1;
                } else if (ele < arr[mid]) {
                    high = mid - 1;
                } else {
                    low = mid + 1;
                }
            }
            return ans;
        }
    }

    private static class arrays {
        // Merge sort
        static void merge(int arr[], int l, int m, int r) {
            int n1 = m - l + 1;
            int n2 = r - m;
            int L[] = new int[n1];
            int R[] = new int[n2];
            for (int i = 0; i < n1; ++i)
                L[i] = arr[l + i];
            for (int j = 0; j < n2; ++j)
                R[j] = arr[m + 1 + j];
            int i = 0, j = 0;
            int k = l;
            while (i < n1 && j < n2) {
                if (L[i] <= R[j]) {
                    arr[k] = L[i];
                    i++;
                } else {
                    arr[k] = R[j];
                    j++;
                }
                k++;
            }

            while (i < n1) {
                arr[k] = L[i];
                i++;
                k++;
            }

            while (j < n2) {
                arr[k] = R[j];
                j++;
                k++;
            }
        }

        static void sort(int arr[], int l, int r) {
            if (l < r) {
                int m = (l + r) / 2;
                sort(arr, l, m);
                sort(arr, m + 1, r);
                merge(arr, l, m, r);
            }
        }

        static void sort(int[] arr) {
            sort(arr, 0, arr.length - 1);
        }
    }

    private static class UnionFindDisjointSet {
        int[] parent;
        int[] size;
        int n;
        int size1;

        public UnionFindDisjointSet(int n) {
            this.n = n;
            this.parent = new int[n];
            this.size = new int[n];
            for (int i = 0; i < n; i++) {
                parent[i] = i;
            }

            for (int i = 0; i < n; i++) {
                size[i] = 1;
            }

            this.size1 = n;
        }

        private int numDisjointSets() {
            System.out.println(size1);
            return size1;
        }

        private boolean find(int a, int b) {
            int rootA = root(a);
            int rootB = root(b);
            if (rootA == rootB) {
                return true;
            }
            return false;
        }

        private int root(int b) {
            if (parent[b] != b) {
                return parent[b] = root(parent[b]);
            }
            return b;
        }

        private void union(int a, int b) {
            int rootA = root(a);
            int rootB = root(b);
            if (rootA == rootB) {
                return;
            }

            if (size[rootA] < size[rootB]) {
                parent[rootA] = parent[rootB];
                size[rootB] += size[rootA];
            } else {
                parent[rootB] = parent[rootA];
                size[rootA] += size[rootB];
            }
            size1--;
            System.out.println(Arrays.toString(parent));
        }
    }

    private static class SegTree {
        int[] st;
        int[] arr;

        public SegTree(int[] arr) {
            this.arr = arr;
            int size = (int) Math.ceil(Math.log(arr.length) / Math.log(2));
            st = new int[(int) ((2 * Math.pow(2, size)) - 1)];
            buildSegmentTree(1, 0, arr.length - 1);
        }

        //**********JUST CALL THE CONSTRUCTOR, THIS FUNCTION WILL BE CALLED AUTOMATICALLY******
        private void buildSegmentTree(int index, int L, int R) {
            if (L == R) {
                st[index] = arr[L];
                return;
            }

            buildSegmentTree(index * 2, L, (L + R) / 2);
            buildSegmentTree(index * 2 + 1, (L + R) / 2 + 1, R);
//          Replace this line if you want to change the function of the Segment tree.
            st[index] = Math.min(st[index * 2], st[index * 2 + 1]);
        }

        //***********We have to use this function **************
        private int Query(int queL, int queR) {
            return Query1(1, 0, arr.length - 1, queL, queR);
        }

        //This is a helper function.
        //************* DO NOT USE THIS ****************
        private int Query1(int index, int segL, int segR, int queL, int queR) {
            if (queL > segR || queR < segL) {
                return -1;
            }

            if (queL <= segL && queR >= segR) {
                return st[index];
            }

            int ans1 = Query1(index * 2, segL, (segL + segR) / 2, queL, queR);
            int ans2 = Query1(index * 2 + 1, (segL + segR) / 2 + 1, segR, queL, queR);
            if (ans1 == -1) {
                return ans2;
            }

            if (ans2 == -1) {
                return ans1;
            }
//             Segment tree implemented for range minimum query. Change the below line to change the function.
            return Math.min(ans1, ans2);
        }

        private void update(int idx, int val) {
            update1(1, 0, arr.length - 1, idx, val);
        }

        private void update1(int node, int queL, int queR, int idx, int val) {
            // idx - index to be updated in the array
            // node - index to be updated in the seg tree
            if (queL == queR) {
                // Leaf node
                arr[idx] += val;
                st[node] += val;
            } else {
                int mid = (queL + queR) / 2;
                if (queL <= idx && idx <= mid) {
                    // If idx is in the left child, recurse on the left child
                    update1(2 * node, queL, mid, idx, val);
                } else {
                    // if idx is in the right child, recurse on the right child
                    update1(2 * node + 1, mid + 1, queR, idx, val);
                }
                // Internal node will have the min of both of its children
                st[node] = Math.min(st[2 * node], st[2 * node + 1]);
            }
        }
    }

    private static class FastReader {
        InputStream is;

        public FastReader(boolean onlineJudge) {
            is = onlineJudge ? System.in : new ByteArrayInputStream(INPUT.getBytes());
        }

        byte[] inbuf = new byte[1024];
        public int lenbuf = 0, ptrbuf = 0;

        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++];
        }

        boolean isSpaceChar(int c) {
            return !(c >= 33 && c <= 126);
        }

        int skip() {
            int b;
            while ((b = readByte()) != -1 && isSpaceChar(b))
                ;
            return b;
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        char nextChar() {
            return (char) skip();
        }

        String next() {
            int b = skip();
            StringBuilder sb = new StringBuilder();
            while (!(isSpaceChar(b))) { // when nextLine, (isSpaceChar(b) && b != ' ')
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }

        String nextLine() {
            int b = skip();
            StringBuilder sb = new StringBuilder();
            while ((!isSpaceChar(b) || b == ' ')) { // when nextLine, (isSpaceChar(b) && b != ' ')
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }

        char[] next(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);
        }

        int nextInt() {
            int num = 0, 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();
            }
        }

        long nextLong() {
            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();
            }
        }

        char[][] nextMatrix(int n, int m) {
            char[][] map = new char[n][];
            for (int i = 0; i < n; i++)
                map[i] = next(m);
            return map;
        }

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

        long[] nextLongArray(int n) {
            long[] a = new long[n];
            for (int i = 0; i < n; i++)
                a[i] = nextLong();
            return a;
        }

        int[][] next2DInt(int n, int m) {
            int[][] arr = new int[n][];
            for (int i = 0; i < n; i++) {
                arr[i] = nextIntArray(m);
            }
            return arr;
        }

        long[][] next2DLong(int n, int m) {
            long[][] arr = new long[n][];
            for (int i = 0; i < n; i++) {
                arr[i] = nextLongArray(m);
            }
            return arr;
        }

        int[] shuffle(int[] arr) {
            Random r = new Random();
            for (int i = 1, j; i < arr.length; i++) {
                j = r.nextInt(i);
                arr[i] = arr[i] ^ arr[j];
                arr[j] = arr[i] ^ arr[j];
                arr[i] = arr[i] ^ arr[j];
            }
            return arr;
        }

        int[] uniq(int[] arr) {
            Arrays.sort(arr);
            int[] rv = new int[arr.length];
            int pos = 0;
            rv[pos++] = arr[0];
            for (int i = 1; i < arr.length; i++) {
                if (arr[i] != arr[i - 1]) {
                    rv[pos++] = arr[i];
                }
            }
            return Arrays.copyOf(rv, pos);
        }
    }

}
