aoc2021/d09/d09_2.py

import sys
L = list(map(lambda s: [9]+list(map(int, s))+[9] ,sys.stdin.read().splitlines()))
W = len(L[0])
L = [[9]*W] + L + [[9]*W]
H = len(L)
def printgrid():
	for row in L:
		print("".join(map(str,row)))
def neigh(x,y,W:set):
	p = L[x][y]
	if p<9:
		W.add((x,y))
		for (i,j) in [(0,1),(1,0),(-1,0),(0,-1)]:
			if L[x+i][y+j]>p and (x+i,y+j) not in W:
				neigh(x+i,y+j,W)
#printgrid()
S = []
for x in range(1,H-1):
	for y in range(1,W-1):
		V = set()
		neigh(x,y,V)
		S.append(len(V))
		#print(V)
#print(S)
print(sorted(S)[-3:])