lib C fun strtoll(s : UInt8*, p : UInt8**, b : Int32) : Int64 end class String def to_i64 C.strtoll(self, nil, 10) end end INF = 10i64 ** 9 # a -> less than b def calc(a, b, d) if a < b 0i64 else res = (a - b) // d + 1 {a - res*d, 0i64}.max < b ? res : INF end end def solve(a, b, c, d) a, b, c = [a, b, c].map { |i| {i, 0i64}.max } if [a, b, c].count { |i| i == 0 } >= 2 INF elsif a == b {solve(a - d, b, c, d) + 1, solve(a, b - d, c, d) + 1}.min elsif a == c {solve(a - d, b, c, d) + 1, solve(a, b, c - d, d) + 1}.min elsif b == c {solve(a, b - d, c, d) + 1, solve(a, b, c - d, d) + 1}.min else if (b > a && b > c) || (b < a && b < c) 0i64 else {calc(a, b, d) + calc(c, b, d), calc(b, {a, c}.min, d)}.min end end end d, a, b, c = (1..4).map { read_line.to_i64 } ans = solve(a, b, c, d) puts ans < INF ? ans : -1