a, b, s = map(int, input().split())
if abs(a - s) <= abs(b - s):
    print(abs(a - s) + s)
elif a == 0:
    print(abs(b - s) + s - 1 + abs(a - 1) + 1)
else:
    print(abs(b - s) + min(s - 1 + abs(a - 1) + 1, abs(a - s) + a))