Problem: Welcome to another task about breaking the code lock! Explorers Whitfield and Martin came across an unusual safe, inside of which, according to rumors, there are untold riches, among which one can find the solution of the problem of discrete logarithm!

Of course, there is a code lock is installed on the safe. The lock has a screen that displays a string of n lowercase Latin letters. Initially, the screen displays string s. Whitfield and Martin found out that the safe will open when string t will be displayed on the screen.

The string on the screen can be changed using the operation «shift x». In order to apply this operation, explorers choose an integer x from 0 to n inclusive. After that, the current string p = αβ changes to βRα, where the length of β is x, and the length of α is n - x. In other words, the suffix of the length x of string p is reversed and moved to the beginning of the string. For example, after the operation «shift 4» the string «abcacb» will be changed with string «bcacab », since α = ab, β = cacb, βR = bcac.

Explorers are afraid that if they apply too many operations «shift», the lock will be locked forever. They ask you to find a way to get the string t on the screen, using no more than 6100 operations.

Input

The first line contains an integer n, the length of the strings s and t (1 ≤ n ≤ 2 000).

After that, there are two strings s and t, consisting of n lowercase Latin letters each.

Output

If it is impossible to get string t from string s using no more than 6100 operations «shift», print a single number  - 1.

Otherwise, in the first line output the number of operations k (0 ≤ k ≤ 6100). In the next line output k numbers xi corresponding to the operations «shift xi» (0 ≤ xi ≤ n) in the order in which they should be applied.

Examples

Input

6
abacbb
babcba


Output

4
6 3 2 3


Input

3
aba
bba


Output

-1

Solution (in JAVA):

Solution:
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.PrintStream;
import java.util.Arrays;
import java.io.BufferedWriter;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        OutputWriter out = new OutputWriter(outputStream);
        TaskC solver = new TaskC();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskC {
        List<Integer> moves;

        char[] move(int idx, char[] c) {
            if (idx <= 0) {
                return c;
            }
            moves.add(idx);
            char[] nxt = new char[c.length];
            for (int i = 0; i < idx; i++) {
                nxt[i] = c[c.length - i - 1];
            }
            for (int i = idx; i < c.length; i++) {
                nxt[i] = c[i - idx];
            }
            return nxt;
        }

        public void solve(int testNumber, InputReader in, OutputWriter out) {
            int n = in.nextInt();
            char[] s1 = in.next().toCharArray();
            char[] s2 = in.next().toCharArray();
            int[] f = new int[26];
            for (int i = 0; i < n; i++) {
                f[s1[i] - 'a']++;
                f[s2[i] - 'a']--;
            }
            for (int i = 0; i < 26; i++) {
                if (f[i] != 0) {
                    out.println(-1);
                    return;
                }
            }

            moves = new ArrayList<>();
            boolean back = true;
            int h = n / 2;

            for (int i = 0; i < n; i++) {
                int want;
                if (i % 2 == 0) {
                    want = h - (i / 2) - (1 - (n % 2));
                } else {
                    want = h + (i / 2) + (n % 2);
                }
                for (int j = i; j < n; j++) {
                    if (s1[j] == s2[want]) {
                        s1 = move(n - j, s1);
                        s1 = move(n - i - (n - j), s1);
                        s1 = move(n, s1);
                        break;
                    }
                }

                Debug.print(moves, i, want, s1, s2);
            }
            if (n % 2 == 1) s1 = move(n, s1);
//        for (int suffix = n-1; suffix >= 0; suffix--) {
//            if (back) {
//                if (s1[suffix] == s2[suffix]) continue;
//                for (int j = 0; j < suffix; j++) {
//                    if (s1[j] == s2[suffix]) {
//                        s1 = move(n-j-1, s1);
//                        s1 = move(j+1, s1);
//                        s1 = move(n-suffix-1, s1);
//                        break;
//                    }
//                }
//                back = !back;
//            } else {
//                if (s1[n-suffix-1] == s2[suffix]) continue;
//                for (int j = 0; j < suffix; j++) {
//                    if (s1[n-j-1] == s2[suffix]) {
//                        s1 = move(j, s1);
//                        s1 = move(n-j, s1);
//                        s1 = move(j, s1);
//                        break;
//                    }
//                }
//                back = !back;
//            }
//        }


            out.println(moves.size());
            boolean first = true;
            for (int j : moves) {
                if (!first) out.print(" ");
                first = false;
                out.print(j);
            }
            out.println();
        }

    }

    static class Debug {
        public static boolean DEBUG;

        static {
            try {
                DEBUG = System.getProperty("user.dir").contains("Dropbox");
            } catch (Exception e) {
                DEBUG = false;
            }
        }

        private static ArrayList<String> getParams() {
            StackTraceElement[] t = Thread.currentThread().getStackTrace();
            StackTraceElement up = t[3];

            ArrayList<String> ret = new ArrayList<>();
            String qqq = up.toString();
            ret.add("." + up.getMethodName() + qqq.substring(qqq.indexOf("("), qqq.length()));
            try {
                BufferedReader br = new BufferedReader(new FileReader(
                        new File("src/" + up.getClassName().replaceAll("\\.", "/") + ".java")));
                int g = up.getLineNumber();
                while (--g > 0) br.readLine();
                String q = br.readLine();
                String[] ss = q.split("Debug\\.print\\(");
                String[] qq = ss[1].substring(0, ss[1].lastIndexOf(")")).split(",");
                for (int i = 0; i < qq.length; i++) {
                    ret.add(qq[i].trim());
                }
            } catch (Exception e) {
            }
            for (int i = 0; i < 100; i++) ret.add("???");
            return ret;
        }

        private static String toString(Object o) {
            if (o == null) {
                return "null";
            } else if (o instanceof Object[]) {
                return Arrays.toString((Object[]) o);
            } else if (o instanceof char[]) {
                return new String((char[]) o);
            } else if (o instanceof int[]) {
                return Arrays.toString((int[]) o);
            } else if (o instanceof long[]) {
                return Arrays.toString((long[]) o);
            } else if (o instanceof double[]) {
                return Arrays.toString((double[]) o);
            } else {
                return o.toString();
            }
        }

        public static void print(Object... x) {
            if (!DEBUG) return;
            ArrayList<String> s = getParams();
            System.out.print(s.get(0) + ": ");
            for (int i = 0; i < x.length; i++) {
                System.out.print(s.get(i + 1) + " = " + toString(x[i]));
                if (i != x.length - 1) System.out.print(", ");
            }
            System.out.println();
        }

    }

    static class OutputWriter {
        private final PrintWriter writer;

        public OutputWriter(OutputStream outputStream) {
            writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
        }

        public OutputWriter(Writer writer) {
            this.writer = new PrintWriter(writer);
        }

        public void print(Object... objects) {
            for (int i = 0; i < objects.length; i++) {
                if (i != 0) {
                    writer.print(' ');
                }
                writer.print(objects[i]);
            }
        }

        public void println() {
            writer.println();
        }

        public void close() {
            writer.close();
        }

        public void print(int i) {
            writer.print(i);
        }

        public void println(int i) {
            writer.println(i);
        }

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1 << 16];
        private int curChar;
        private int numChars;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (this.numChars == -1) {
                throw new InputMismatchException();
            } else {
                if (this.curChar >= this.numChars) {
                    this.curChar = 0;

                    try {
                        this.numChars = this.stream.read(this.buf);
                    } catch (IOException var2) {
                        throw new InputMismatchException();
                    }

                    if (this.numChars <= 0) {
                        return -1;
                    }
                }

                return this.buf[this.curChar++];
            }
        }

        public int nextInt() {
            int c;
            for (c = this.read(); isSpaceChar(c); c = this.read()) {
                ;
            }

            byte sgn = 1;
            if (c == 45) {
                sgn = -1;
                c = this.read();
            }

            int res = 0;

            while (c >= 48 && c <= 57) {
                res *= 10;
                res += c - 48;
                c = this.read();
                if (isSpaceChar(c)) {
                    return res * sgn;
                }
            }

            throw new InputMismatchException();
        }

        public String next() {
            int c;
            while (isSpaceChar(c = this.read())) {
                ;
            }

            StringBuilder result = new StringBuilder();
            result.appendCodePoint(c);

            while (!isSpaceChar(c = this.read())) {
                result.appendCodePoint(c);
            }

            return result.toString();
        }

        public static boolean isSpaceChar(int c) {
            return c == 32 || c == 10 || c == 13 || c == 9 || c == -1;
        }

    }
}