{"trustable":true,"sections":[{"title":"","value":{"format":"HTML","content":" A well-known application of suffix trees is solving the following problem: given a string, find the number of distinct substrings that the string has. For example, the string \"abac\" has 9 distinct substrings: \"a\", \"b\", \"c\", \"ab\", \"ba\", \"ac\", \"aba\", \"bac\", \"abac\".\u003cbr\u003eYou are faced with generating testcases for this problem.\u003cbr\u003eMore specifically, you should find the shortest string consisting only of lowercase English letters that has exactly the given amount \u003ci\u003en\u003c/i\u003e of distinct substrings. Among several shortest strings, choose the lexicographically smallest one.\u003cbr\u003e\u003cdiv align\u003d\"left\" style\u003d\"margin-top: 1.0em;\"\u003e\u003cb\u003eInput\u003c/b\u003e\u003c/div\u003eFirst and only line of the input file contains an integer \u003ci\u003en\u003c/i\u003e, 1 ≤ \u003ci\u003en\u003c/i\u003e ≤ 300.\u003cbr\u003e\u003cdiv align\u003d\"left\" style\u003d\"margin-top: 1.0em;\"\u003e\u003cb\u003eOutput\u003c/b\u003e\u003c/div\u003eIn the only line of the output file write the sought string.\u003cbr\u003e"}},{"title":"Sample 1","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e5\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003eaab\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}