source_code: import java.io.OutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.io.BufferedWriter;
  import java.util.InputMismatchException;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.io.Writer;
  import java.io.OutputStreamWriter;
  import java.io.InputStream;
  
  /**
   * Built using CHelper plug-in
   * Actual solution is at the top
   *
   * @author ilyakor
   */
  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 {
          public void solve(int testNumber, InputReader in, OutputWriter out) {
              int n = in.nextInt();
              int r = in.nextInt();
              ArrayList<PointDouble> centers = new ArrayList<>();
              ArrayList<Integer> xs = new ArrayList<>();
              for (int i = 0; i < n; ++i) {
                  int x = in.nextInt();
                  double y = r;
                  for (int j = 0; j < centers.size(); j++) {
                      int ox = xs.get(j);
                      if (Math.abs(ox - x) > 2 * r) continue;
                      PointDouble c = centers.get(j);
                      double t = Math.abs(ox - x);
                      double h = Math.sqrt(Math.abs(4.0 * r * r - t * t));
                      double val = c.y + h;
                      if (y < val) y = val;
                  }
                  out.print(String.format("%.20f ", y));
                  centers.add(new PointDouble(x, y));
                  xs.add(x);
              }
              out.printLine();
          }
  
      }
  
      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 printLine(Object... objects) {
              print(objects);
              writer.println();
          }
  
          public void close() {
              writer.close();
          }
  
      }
  
      static class InputReader {
          private InputStream stream;
          private byte[] buffer = new byte[10000];
          private int cur;
          private int count;
  
          public InputReader(InputStream stream) {
              this.stream = stream;
          }
  
          public static boolean isSpace(int c) {
              return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
          }
  
          public int read() {
              if (count == -1) {
                  throw new InputMismatchException();
              }
              try {
                  if (cur >= count) {
                      cur = 0;
                      count = stream.read(buffer);
                      if (count <= 0)
                          return -1;
                  }
              } catch (IOException e) {
                  throw new InputMismatchException();
              }
              return buffer[cur++];
          }
  
          public int readSkipSpace() {
              int c;
              do {
                  c = read();
              } while (isSpace(c));
              return c;
          }
  
          public int nextInt() {
              int sgn = 1;
              int c = readSkipSpace();
              if (c == '-') {
                  sgn = -1;
                  c = read();
              }
              int res = 0;
              do {
                  if (c < '0' || c > '9') {
                      throw new InputMismatchException();
                  }
                  res = res * 10 + c - '0';
                  c = read();
              } while (!isSpace(c));
              res *= sgn;
              return res;
          }
  
      }
  
      static class PointDouble {
          public double x;
          public double y;
  
          public PointDouble(double x, double y) {
              this.x = x;
              this.y = y;
          }
  
          public PointDouble() {
              x = 0;
              y = 0;
          }
  
      }
  }
  
  