B'Petya loves lucky numbers. We all know that lucky numbers are the positive integers whose decimal representations contain only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not. Petya recently learned to determine whether a string of lowercase Latin letters is lucky. For each individual letter all its positions in the string are written out in the increasing order. This results in 26 lists of numbers; some of them can be empty. A string is considered lucky if and only if in each list the absolute difference of any two adjacent numbers is a lucky number. For example, let 's consider string "zbcdzefdzc". The lists of positions of equal letters are: This string is lucky as all differences are lucky numbers. For letters z: 5 xe2 x80 x89- xe2 x80 x891 xe2 x80 x89= xe2 x80 x894, 9 xe2 x80 x89- xe2 x80 x895 xe2 x80 x89= xe2 x80 x894, for letters c: 10 xe2 x80 x89- xe2 x80 x893 xe2 x80 x89= xe2 x80 x897, for letters d: 8 xe2 x80 x89- xe2 x80 x894 xe2 x80 x89= xe2 x80 x894. Note that if some letter occurs only once in a string, it doesn 't influence the string 's luckiness after building the lists of positions of equal letters. The string where all the letters are distinct is considered lucky. Find the lexicographically minimal lucky string whose length equals n. The single line contains a positive integer n (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89105) -- the length of the sought string. Print on the single line the lexicographically minimal lucky string whose length equals n. The lexical comparison of strings is performed by the < operator in modern programming languages. String a is lexicographically less than string b if exists such i (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89i xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n), that ai xe2 x80 x89< xe2 x80 x89bi, and for any j (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89j xe2 x80 x89< xe2 x80 x89i) aj xe2 x80 x89= xe2 x80 x89bj.'...