int_data = input()

sp_int = int_data.split(" ")

first_sab = int(sp_int[0])
sec_sab = int(sp_int[1])
las_day = int(sp_int[2])

result = las_day

if first_sab <= las_day:
	result = result -1

if sec_sab <= las_day:
	result = result -1


print(result)