var grid = require("fs").readFileSync("input.txt").toString().split("\n").filter(a=>(a)).reverse().map(a=>(a.split("")));
var dirs = [[0, 1], [1, 0], [0, -1], [-1, 0]];
var dir = 0;
var x = Math.floor(grid.length/2);
var y = Math.floor(grid.length/2);
var numInfected = 0;

for(var i = 0; i < 10000000; i++){
	var clean = true;
	if(grid[y]){
		if(!grid[y][x]){
			grid[y][x] = ".";
		}
	}
	else{
		grid[y] = [];
		grid[y][x] = ".";
	}

	var states = [".", "W", "#", "F"];
	var dirChanges = [-1, 0, 1, 2];
	dir += dirChanges[states.indexOf(grid[y][x])];
	grid[y][x] = states[(states.indexOf(grid[y][x])+1) % 4];
	if(grid[y][x] == "#"){
		numInfected++;
	}

	dir = (dir+4)%4;
	x += dirs[dir][0];
	y += dirs[dir][1];
}
console.log(numInfected);