B'Polycarpus has a ribbon, its length is n. He wants to cut the ribbon in a way that fulfils the following two conditions: Help Polycarpus and find the number of ribbon pieces after the required cutting. The first line contains four space-separated integers n, a, b and c (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n, xe2 x80 x89a, xe2 x80 x89b, xe2 x80 x89c xe2 x80 x89 xe2 x89 xa4 xe2 x80 x894000) -- the length of the original ribbon and the acceptable lengths of the ribbon pieces after the cutting, correspondingly. The numbers a, b and c can coincide. Print a single number -- the maximum possible number of ribbon pieces. It is guaranteed that at least one correct ribbon cutting exists. In the first example Polycarpus can cut the ribbon in such way: the first piece has length 2, the second piece has length 3. In the second example Polycarpus can cut the ribbon in such way: the first piece has length 5, the second piece has length 2.'...