data = []
for line in open("input"):
    words = line.replace(":", "").replace(",","").split()
    coords = [int(w[w.index('=')+1:]) for w in words if '=' in w]
    data.append(coords)
#print(data)

none = set()

Y = 10
Y = 2000000

for sx,sy,bx,by in data:
    dx = abs(sx-bx)
    dy = abs(sy-by)
    dist = dx+dy
    y = Y-sy
    for x in range(-dist,dist+1):
        if abs(x)+abs(y) <= dist:
            p = (sx+x, sy+y)
            if p != (bx,by):
                none.add(sx+x)

print(len(none))