A, B, S = map(int, input().split()) def f(p, a, b): if p == 1: return abs(1 - a) + 1 ax = abs(p - a) bx = abs(p - b) if ax <= bx: return ax + p cands = [] cands.append(bx + (p-1) + f(1, a, b)) if a >= 1: cands.append(bx + ax + f(a, a, a)) return min(cands) ans = f(S, A, B) print(ans)