#advent of code 2020
#day 03

grid = dict();
limY = 0;
limX = 0;
PuzzleInput = open("03.in","r");
for y,line in enumerate(PuzzleInput):
	for x, c in enumerate(line):
		grid[(x,y)] = c;
		limX = max(limX,x);
	limY = max(limY,y);
PuzzleInput.close();
slopes = [(1,1),(3,1),(5,1),(7,1),(1,2)];
p1 = 0;
p2 = 1;
for slope in slopes:
	stepX, stepY = slope;
	MyPosX = 0;
	MyPosY = 0;	
	trees = 0;
	while MyPosY < limY :
		MyPosX += stepX;
		MyPosY += stepY;
		if grid[(MyPosX%limX),MyPosY] == "#": trees +=1;
	p2 *= trees;
	if slope == (3,1): p1 += trees;
print("part 1 = ",p1);
print("part 2 = ",p2);