def can(v, x, stop):
tram_time = stop // v
petro_time = abs(x - stop)
return tram_time >= petro_time
v, x, a, b = map(int, input().split())
can_first = can(v, x, a)
can_second = can(v, x, b)
if can_first and can_second:
if abs(x - a) <= abs(x - b):
print("1")
else:
print("2")
elif can_first or can_second:
if can_first:
print("1")
else:
print("2")
else:
print("-1")
