source_code: import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.PrintWriter;
  import java.math.BigInteger;
  import java.util.*;
  
  public class C {
  
      public static void main(String[] args) {
  
          MyScanner in = new MyScanner();
          PrintWriter out = new PrintWriter(System.out);
          int n = in.nextInt();
          int r = in.nextInt();
  
          double[] y = new double[n];
          int[] x = new int[n];
  
          for(int i=0;i<n;++i){
              x[i] = in.nextInt();
              double bestY = r;
              for(int j=0;j<i;++j){
                  if(Math.abs(x[i]-x[j]) <= 2*r){
                      double ny = y[j] + Math.sqrt(4*r*r - (x[i]-x[j])*(x[i]-x[j]));
                      if(ny > bestY){
                          bestY = ny;
                      }
                  }
              }
              y[i] = bestY;
          }
  
          for(int i=0;i<n;++i){
              out.println(y[i]);
          }
  
          out.close();
  
      }
  
  
      // -----------MyScanner class for faster input----------
      public static class MyScanner {
          BufferedReader br;
          StringTokenizer st;
  
          public MyScanner() {
              br = new BufferedReader(new InputStreamReader(System.in));
          }
  
          String next() {
              while (st == null || !st.hasMoreElements()) {
                  try {
                      st = new StringTokenizer(br.readLine());
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              }
              return st.nextToken();
          }
  
          int nextInt() {
              return Integer.parseInt(next());
          }
  
          long nextLong() {
              return Long.parseLong(next());
          }
  
          double nextDouble() {
              return Double.parseDouble(next());
          }
  
          String nextLine() {
              String str = "";
              try {
                  str = br.readLine();
              } catch (IOException e) {
                  e.printStackTrace();
              }
              return str;
          }
  
      }
      // --------------------------------------------------------
  
  }