#include <iostream>
#include <vector>
#include <string>
#include <sstream>

using namespace std;

int dx[] = {0, -1, 0, 1};
int dy[] = {1, 0, -1, 0};

class FractalPicture {
private:
	int x1, y1, x2, y2;
	bool inRec(int x, int y){
		return x1 <= x && x <= x2 && y1 <= y && y <= y2;
	}
public:
	double calc(int sx, int sy, int dir, int len){
		double res = 0.0;
		if(len == 1){
			int x = sx, y = sy;
			if(inRec(x, y)&&inRec(x+dx[dir], y+dy[dir])){
				res += 1.0;
				for(int i=1;i<=3;i+=2){
					if(inRec(x+dx[(dir+i)%4], y+dy[(dir+i)%4])){
						res += 495/3.0;
					}
				}
			}
		} else {
			int x = sx, y = sy;
			for(int i=0;i<len/3*2;i++){
				if(inRec(x, y)&&inRec(x+dx[dir], y+dy[dir])) res += 1.0;
				x += dx[dir];
				y += dy[dir];
			}
			res += calc(x, y, (dir+3)%4, len/3);
			res += calc(x, y, (dir+0)%4, len/3);
			res += calc(x, y, (dir+1)%4, len/3);
		}
		return res;
	}
	double getLength(int _x1, int _y1, int _x2, int _y2) {
		x1 = _x1, y1 = _y1, x2 = _x2, y2 = _y2;
		return calc(0, 0, 0, 81);
	}
};