Problem: Recall that the bracket sequence is considered regular if it is possible to insert symbols '+' and '1' into it so that the result is a correct arithmetic expression. For example, a sequence "(()())" is regular, because we can get correct arithmetic expression insering symbols '+' and '1': "((1+1)+(1+1))". Also the following sequences are regular: "()()()", "(())" and "()". The following sequences are not regular bracket sequences: ")(", "(()" and "())(()".

In this problem you are given two integers n and k. Your task is to construct a regular bracket sequence consisting of round brackets with length 2·n with total sum of nesting of all opening brackets equals to exactly k. The nesting of a single opening bracket equals to the number of pairs of brackets in which current opening bracket is embedded.

For example, in the sequence "()(())" the nesting of first opening bracket equals to 0, the nesting of the second opening bracket equals to 0 and the nesting of the third opening bracket equal to 1. So the total sum of nestings equals to 1.

Input

The first line contains two integers n and k (1 ≤ n ≤ 3·105, 0 ≤ k ≤ 1018) — the number of opening brackets and needed total nesting.

Output

Print the required regular bracket sequence consisting of round brackets.

If there is no solution print "Impossible" (without quotes).

Examples

Input

3 1


Output

()(())

Input

4 6


Output

(((())))

Input

2 5


Output

Impossible

Note

The first example is examined in the statement.

In the second example the answer is "(((())))". The nesting of the first opening bracket is 0, the nesting of the second is 1, the nesting of the third is 2, the nesting of fourth is 3. So the total sum of nestings equals to 0 + 1 + 2 + 3 = 6.

In the third it is impossible to construct a regular bracket sequence, because the maximum possible total sum of nestings for two opening brackets equals to 1. This total sum of nestings is obtained for the sequence "(())".

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.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.FileNotFoundException;
import java.io.File;
import java.util.StringTokenizer;
import java.io.Writer;
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);
    C solver = new C();
    solver.solve(1, in, out);
    out.close();
  }

  static class C extends SimpleSavingChelperSolution {
    public void solve(int testNumber, InputReader in, OutputWriter out) {
      wrapSolve(testNumber, in, out);
    }


    public void solve(int testNumber) {
      int n = in.nextInt();
      long k = in.nextLong();

      long left = k;
      StringBuilder sb = new StringBuilder();

      long current = -1;

      for (int i = 0; i < n; i++) {
        if (current + 1 <= left) {
          current++;
          left -= current;
          sb.append('(');

          continue;
        }

        while (current + 1 > left) {
          sb.append(')');
          current--;
        }

        current++;
        left -= current;
        sb.append('(');
      }

      while (current + 1 > 0) {
        sb.append(')');
        current--;
      }

      if (left > 0) {
        out.println("Impossible");
        return;
      }

      out.println(sb.toString());
    }

  }

  static abstract class SimpleSavingChelperSolution extends SavingChelperSolution {

    public String processOutputPreCheck(int testNumber, String output) {
      return output;
    }


    public String processOutputPostCheck(int testNumber, String output) {
      return output;
    }

  }

  static abstract class SavingChelperSolution {
    protected int testNumber;
    public InputReader in;
    public OutputWriter out;
    private OutputWriter toFile;
    private boolean local = new File("chelper.properties").exists();
    public OutputWriter debug;

    {
      if (local) {
        debug = new OutputWriter(System.out);
      } else {
        debug = new OutputWriter(new OutputStream() {

          public void write(int b) {
          }
        });
      }
    }

    public SavingChelperSolution() {
      try {
        toFile = new OutputWriter("last_test_output.txt");
      } catch (FileNotFoundException e) {
        throw new RuntimeException(e);
      }
    }

    public abstract void solve(int testNumber);

    public abstract String processOutputPreCheck(int testNumber, String output);

    public abstract String processOutputPostCheck(int testNumber, String output);

    public void wrapSolve(int testNumber, InputReader in, OutputWriter out) {
      this.testNumber = testNumber;

      ByteArrayOutputStream substituteOutContents = new ByteArrayOutputStream();
      OutputWriter substituteOut = new OutputWriter(substituteOutContents);

      this.in = in;
      this.out = substituteOut;

      solve(testNumber);
      substituteOut.flush();

      String result = substituteOutContents.toString();

      result = processOutputPreCheck(testNumber, result);
      out.print(result);
      out.flush();

      if (local) {
        debug.flush();

        result = processOutputPostCheck(testNumber, result);
        toFile.print(result);
        toFile.flush();
      }
    }

  }

  static class OutputWriter extends PrintWriter {

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

    public OutputWriter(String fileName) throws FileNotFoundException {
      super(fileName);
    }

    public OutputWriter(OutputStream outputStream) {
      super(outputStream);
    }

    public OutputWriter(Writer writer) {
      super(writer);
    }

  }

  static class InputReader {
    private BufferedReader br;
    private StringTokenizer in;

    public InputReader(String fileName) {
      try {
        br = new BufferedReader(new FileReader(fileName));
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }

    public InputReader(InputStream inputStream) {
      br = new BufferedReader(new InputStreamReader(inputStream));
    }

    private boolean hasMoreTokens() {
      while (in == null || !in.hasMoreTokens()) {
        String s = nextLine();
        if (s == null) {
          return false;
        }
        in = new StringTokenizer(s);
      }
      return true;
    }

    public String nextString() {
      return hasMoreTokens() ? in.nextToken() : null;
    }

    public String nextLine() {
      try {
        in = null;
        return br.readLine();
      } catch (Exception e) {
        e.printStackTrace();
        return null;
      }
    }

    public int nextInt() {
      return Integer.parseInt(nextString());
    }

    public long nextLong() {
      return Long.parseLong(nextString());
    }

  }
}