A,B,S=map(int,input().split())

if abs(A-S)<=abs(B-S):
    print(abs(A-S)+S)
else:
    if S==1 and A!=0:
        print(A)
    elif A!=0:
        print(min(abs(B-S)+(S-1)+abs(A-1)+1,abs(B-S)+abs(A-S)+A))
    else:
        print(abs(B-S)+(S-1)+abs(A-1)+1)