package com.zju.edu.cn.test;import java.io.File;import java.io.FileInputStream;import java.io.InputStream;import java.io.InputStreamReader;import java.util.Scanner;public class Test1 {     static  double forcast(int cycle , int period , double[] historical_data, int next_n, int next_m){    	  double A[][]  = new double[period + next_n + 1][cycle];    	      	  for(int i = 0 ; i < period ; i ++)    		  for(int j = 0 ; j < cycle ; j ++){    			  A[i][j] = historical_data[cycle * i + j];     		  }    	  for(int i = 2 ; i <= next_n + 2 ; i ++)    		  for(int j = 0 ; j < cycle ; j ++){    			  A[i][j] =  (A[i -2][j] + A[i - 1][j])/2;    		  }    	  return   A[next_n + period][next_m] ;       }		  	  public static void main(String[] args) throws Exception{		  File file = new File("D:\\in.txt");			InputStream is = new FileInputStream(file);			Scanner in = new Scanner(new InputStreamReader(is));	    	int cycle , period,next_n,next_m;	    	cycle = in.nextInt();	    	period = in.nextInt();	    	double  historical_data[] = new double[cycle * period];	    	for(int i = 0 ; i < cycle * period; i ++)	    		historical_data[i] = in.nextDouble();	    	next_n = in.nextInt();	    	next_m = in.nextInt();	    	double result = forcast(cycle, period,historical_data,next_n,next_m);	    	System.out.println(result);	  }    }