Ivan has an array consisting of n elements. Each of the elements is an integer from 1 to n.

Recently Ivan learned about permutations and their lexicographical order. Now he wants to change (replace) minimum number of elements in his array in such a way that his array becomes a permutation (i.e. each of the integers from 1 to n was encountered in his array exactly once). If there are multiple ways to do it he wants to find the lexicographically minimal permutation among them.

Thus minimizing the number of changes has the first priority, lexicographical minimizing has the second priority.

In order to determine which of the two permutations is lexicographically smaller, we compare their first elements. If they are equal — compare the second, and so on. If we have two permutations x and y, then x is lexicographically smaller if xi < yi, where i is the first index in which the permutations x and y differ.

Determine the array Ivan will obtain after performing all the changes.

Input

The first line contains an single integer n (2 ≤ n ≤ 200 000) — the number of elements in Ivan's array.

The second line contains a sequence of integers a1, a2, ..., an (1 ≤ ai ≤ n) — the description of Ivan's array.

Output

In the first line print q — the minimum number of elements that need to be changed in Ivan's array in order to make his array a permutation. In the second line, print the lexicographically minimal permutation which can be obtained from array with q changes.

Examples

Input

4
3 2 2 3


Output

2
1 2 4 3 


Input

6
4 5 6 3 2 1


Output

0
4 5 6 3 2 1 


Input

10
6 8 4 6 7 1 6 3 4 5


Output

3
2 8 4 6 7 1 9 3 10 5 

Note

In the first example Ivan needs to replace number three in position 1 with number one, and number two in position 3 with number four. Then he will get a permutation [1, 2, 4, 3] with only two changed numbers — this permutation is lexicographically minimal among all suitable. 

In the second example Ivan does not need to change anything because his array already is a permutation.
import java.util.*;
 
import javax.lang.model.util.ElementScanner6;
 
import java.io.*;
 
public class Main {
 
    public static void main(String[] args) {
 
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader inp = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        Solver solver = new Solver();
        solver.solve(inp, out);
        out.close();
 
    }
 
 
 
 
 
    static class Solver {
 
        class pair implements Comparable<pair>{
 
            int i;
            long dist;
            public pair(int i,long dist)
            {
                this.i=i;
                this.dist=dist;
            }
 
            public int compareTo(pair p)
            {
                return Long.compare(this.dist,p.dist);
            }
 
        }
 
        class Node implements Comparable < Node > {
            int i;
            int cnt;
 
            Node(int i, int cnt) {
                this.i = i;
                this.cnt = cnt;
            }
 
            public int compareTo(Node n) {
                if (this.cnt == n.cnt) {
                    return Integer.compare(this.i, n.i);
                }
                return Integer.compare(this.cnt, n.cnt);
            }
        }
 
        public boolean done(int[] sp, int[] par) {
            int root;
 
            root = findSet(sp[0], par);
 
            for (int i = 1; i < sp.length; i++) {
                if (root != findSet(sp[i], par))
                    return false;
            }
            return true;
        }
        public int findSet(int i, int[] par) {
            int x = i;
            boolean flag = false;
            while (par[i] >= 0) {
                flag = true;
                i = par[i];
            }
            if (flag)
                par[x] = i;
            return i;
        }
 
        public void unionSet(int i, int j, int[] par) {
            int x = findSet(i, par);
            int y = findSet(j, par);
            if (x < y) {
                par[y] = x;
            } else {
                par[x] = y;
            }
        }
 
        public long pow(long a, long b, long MOD) {
            if (b == 0) {
                return 1;
            }
            if (b == 1) {
                return a;
            }
            long val = pow(a, b / 2, MOD);
            if (b % 2 == 0) {
                return val * val % MOD;
            } else {
                return val * (val * a % MOD) % MOD;
 
            }
 
        }
 
        public boolean isPrime(int n)
        {
            for(int i=2;i<n;i++)
            {
                if(n%i==0)
                {
                    return false;
                }
            }
            return true;
        }
 
 
        public void minPrimeFactor(int n, int[] s) {
            boolean prime[] = new boolean[n + 1];
            Arrays.fill(prime, true);
            s[1] = 1;
            s[2] = 2;
            for (int i = 4; i <= n; i += 2) {
                prime[i] = false;
                s[i] = 2;
            }
 
            for (int i = 3; i <= n; i += 2) {
                if (prime[i]) {
                    s[i] = i;
                    for (int j = 2 * i; j <= n; j += i) {
                        prime[j] = false;
                        s[j] = i;
                    }
                }
            }
 
        }
 
 
        public void findAllPrime(int n, ArrayList < Node > al, int s[]) {
            int curr = s[n];
            int cnt = 1;
            while (n > 1) {
                n /= s[n];
                if (curr == s[n]) {
                    cnt++;
                    continue;
 
                }
                Node n1 = new Node(curr, cnt);
                al.add(n1);
 
                curr = s[n];
                cnt = 1;
            }
        }
 
 
 
        public int binarySearch(int n, int k) {
            int left = 1;
            int right = 100000000 + 5;
            int ans = 0;
            while (left <= right) {
                int mid = (left + right) / 2;
                if (n / mid >= k) {
                    left = mid + 1;
                    ans = mid;
                } else {
                    right = mid - 1;
                }
            }
 
            return ans;
        }
        public boolean checkPallindrom(String s) {
            char ch[] = s.toCharArray();
 
            for (int i = 0; i < s.length() / 2; i++) {
                if (ch[i] != ch[s.length() - 1 - i])
                    return false;
            }
            return true;
        }
 
 
 
 
        public void remove(ArrayList < Integer > [] al, int x) {
            for (int i = 0; i < al.length; i++) {
                for (int j = 0; j < al[i].size(); j++) {
 
                    if (al[i].get(j) == x)
                        al[i].remove(j);
 
                }
            }
        }
 
        public long gcd(long a, long b) {
            if (a == 0)
                return b;
            return gcd(b % a, a);
        }
 
 
        public void printDivisors(long n, ArrayList < Long > al) {
            // Note that this loop runs till square root 
            for (long i = 1; i <= Math.sqrt(n); i++) {
                if (n % i == 0) {
                    // If divisors are equal, print only one 
                    if (n / i == i) {
                        al.add(i);
                    } else // Otherwise print both 
                    {
                        al.add(i);
                        al.add(n / i);
                    }
 
                }
            }
        }
 
        public static long constructSegment(long seg[], long arr[], int low, int high, int pos) {
            if (low == high) {
                seg[pos] = arr[low];
                return seg[pos];
            }
            int mid = (low + high) / 2;
            long t1 = constructSegment(seg, arr, low, mid, (2 * pos) + 1);
            long t2 = constructSegment(seg, arr, mid + 1, high, (2 * pos) + 2);
            seg[pos] = t1 + t2;
            return seg[pos];
 
        }
        public static long querySegment(long seg[], int low, int high, int qlow, int qhigh, int pos) {
 
            if (qlow <= low && qhigh >= high) {
                return seg[pos];
            } else if (qlow > high || qhigh < low) {
                return 0;
            } else {
                long ans = 0;
                int mid = (low + high) / 2;
                ans += querySegment(seg, low, mid, qlow, qhigh, (2 * pos) + 1);
                ans += querySegment(seg, mid + 1, high, qlow, qhigh, (2 * pos) + 2);
                return ans;
            }
 
        }
        public static int lcs(char[] X, char[] Y, int m, int n) {
            if (m == 0 || n == 0)
                return 0;
            if (X[m - 1] == Y[n - 1])
                return 1 + lcs(X, Y, m - 1, n - 1);
            else
                return Integer.max(lcs(X, Y, m, n - 1), lcs(X, Y, m - 1, n));
        }
 
        public static long recursion(long start, long end, long cnt[], int a, int b) {
 
            long min = 0;
            long count = 0;
            int ans1 = -1;
            int ans2 = -1;
            int l = 0;
            int r = cnt.length - 1;
            while (l <= r) {
                int mid = (l + r) / 2;
                if (cnt[mid] >= start) {
                    ans1 = mid;
                    r = mid - 1;
                } else {
                    l = mid + 1;
                }
            }
 
            l = 0;
            r = cnt.length - 1;
            while (l <= r) {
                int mid = (l + r) / 2;
                if (cnt[mid] <= end) {
                    ans2 = mid;
                    l = mid + 1;
                } else {
                    r = mid - 1;
                }
            }
 
            if (ans1 == -1 || ans2 == -1 || ans2 < ans1) {
                // System.out.println("min1 "+min);
                min = a;
                return a;
 
            } else {
                min = b * (end - start + 1) * (ans2 - ans1 + 1);
            }
            if (start == end) {
                // System.out.println("min "+min);
                return min;
            }
            long mid = (end + start) / 2;
            min = Long.min(min, recursion(start, mid, cnt, a, b) + recursion(mid + 1, end, cnt, a, b));
            // System.out.println("min "+min);
            return min;
        }
 
 
 
 
 
        public int dfs_util(ArrayList < Integer > [] al, boolean vis[], int x, int[] s, int lvl[]) {
 
            vis[x] = true;
            int cnt = 1;
            for (int i = 0; i < al[x].size(); i++) {
 
                if (!vis[al[x].get(i)]) {
                    lvl[al[x].get(i)] = lvl[x] + 1;
                    cnt += dfs_util(al, vis, al[x].get(i), s, lvl);
 
 
                }
 
 
            }
            s[x] = cnt;
            return s[x];
        }
 
        public void dfs(ArrayList[] al, int[] s, int[] lvl) {
 
            boolean vis[] = new boolean[al.length];
            for (int i = 0; i < al.length; i++) {
                if (!vis[i]) {
                    lvl[i] = 1;
                    dfs_util(al, vis, i, s, lvl);
                }
            }
        }
 
        public int[] computeLps(String s)
        {
            int ans[] =new int[s.length()];
            char ch[] = s.toCharArray();
            int n = s.length();
            int i=1;
            int len=0;
            ans[0]=0;
            while(i<n)
            {
                if(ch[i]==ch[len])
                {
                    len++;
                    ans[i]=len;
                    i++;
                }
                else
                {
                    if(len!=0)
                    {
                        len=ans[len-1];
                    }
                    else
                    {
                        ans[i]=len;
                        i++;
                    }
                }
            }
 
            return ans;
 
        }

        public static boolean check(long n ,long b,long t,long k)
        {
            long ref=0;
            long temp=b;

            long i=0;
            


            if(b>=t)
            {

                b-=t;
            }
            else
            {
                return false;
            }

            while(i<k)
            {

                if(i==k-1)
                {
                    if(b>=(n-t))
                    {
                        b-=(n-t);
                    }
                    else if(temp>=(n-t))
                    {
                        b=temp;
                        b-=(n-t);
                        ref++;
                    }
                    else
                    {
                        return false;
                    }
                }
                else
                {
                    if(b>=2*(n-t))
                    {
                        b-=2*(n-t);
                    }
                    else if(temp>=2*(n-t))
                    {
                        b=temp;
                        b-=2*(n-t);
                        ref++;
                    }
                    else
                    {
                        return false;
                    }
                }
                
                i++;
                if(i>=k)
                {
                    break;
                }

                if(i==k-1)
                {
                    if(b>=t)
                    {
                        b-=t;
                    }
                    else if(temp>=t)
                    {
                        ref++;
                        b=temp;
                        b-=t;
                    }
                    else
                    {
                        return false;
                    }
                }
                else
                {
                    if(b>=2*t)
                    {
                        b-=2*t;
                    }
                    else if(temp>=2*t)
                    {
                        b=temp;
                        b-=2*t;
                        ref++;
                    }
                    else
                    {
                        return false;
                    }
                }
                i++;

                

            }
            System.out.println(ref);
            return true;
            
        }
 
 
        private void solve(InputReader inp, PrintWriter out1) {

          
            int n= inp.nextInt();
            int arr[] = new int[n];
            int count[] = new int[n+1];
            for(int i=0;i<n;i++)
            {
                arr[i]=inp.nextInt();
                count[arr[i]]++;
            }
            Queue<Integer> q = new LinkedList<Integer>();
            boolean f[] = new boolean[n+1];
            for(int i=1;i<=n;i++)
            {
                if(count[i]==0)
                {
                    q.add(i);
                }
            }
            int cnt=0;
            for(int i=0;i<n;i++)
            {
                if(count[arr[i]]>1)
                {
                    // System.out.println("hello");
                    int x=q.peek();
                    if(x<arr[i]||f[arr[i]])
                    {
                        count[arr[i]]--;
                        arr[i]=q.poll();
                        
                        cnt++;
                        // System.out.println("hello1");

                    }
                    else
                    {
                        f[arr[i]]=true;

                    }
                }
            }

            out1.println(cnt);
            for(int i=0;i<n;i++)
            {
                out1.print(arr[i]+" ");
            }
        
        }
 
 
}
 
 
    static class InputReader {
        BufferedReader reader;
        StringTokenizer tokenizer;
 
        InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }
 
        String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }
 
        public int nextInt() {
            return Integer.parseInt(next());
        }
 
        public long nextLong() {
            return Long.parseLong(next());
        }
    }
}
class ele implements Comparable < ele > {
    int value;
    int i;
    boolean flag;
    public ele(int value, int i) {
        this.value = value;
        this.i = i;
        this.flag = false;
    }
    public int compareTo(ele e) {
        return Integer.compare(this.value, e.value);
    }
}