A,B,C,D = map(int, input().split())
if A < 0 or A > 100:
	print("Error")
elif B < 0 or B >100:
	print("Error")
elif C < 0 or C >100:
	print("Error")
elif D < 0 or D >100:
	print("Error")
elif C == 0:
	print("Error")
else:
	situ = min(A, B //C, D // (C + 1))
	print(situ)