a, b, s = map(int,input().split())
   
if s == 1:
    print(abs(a-1)+1)
    exit()

if s == a and s == b:
    print(a)
elif s == a and s != b:
    print(a)
elif (s != a and s == b) and a != 0:
    if abs(s-a) > abs(s-1):
        print(abs(b-1) + a)
    else:
        print(abs(b-a) + a)
elif (s != a and s == b) and a == 0:
    print((b - 1) + 2)

else:
    if abs(s-a) == abs(s-b):
        print(abs(s-a)+ s)
    elif abs(s-a) < abs(s-b):
        print(abs(s-a) + s)
    else: 
        if a !=0:
            if abs(s-a) > abs(s-1): 
                print(abs(s-b) + abs(s-1) + a)
            else:
                print(abs(s-b) + abs(s-a) + a)
        else:
            print(abs(s-b) + (s-1) + 2)