Little penguin Polo adores strings. But most of all he adores strings of length *n*.

One day he wanted to find a string that meets the following conditions:
 1.  The string consists of *n* lowercase English letters (that is, the string's length equals *n*), exactly *k* of these letters are distinct. 1.  No two neighbouring letters of a string coincide; that is, if we represent a string as *s* = *s*<sub class="lower-index">1</sub>*s*<sub class="lower-index">2</sub>... *s*<sub class="lower-index">*n*</sub>, then the following inequality holds, *s*<sub class="lower-index">*i*</sub> ≠ *s*<sub class="lower-index">*i* + 1</sub>(1 ≤ *i* &lt; *n*). 1.  Among all strings that meet points 1 and 2, the required string is lexicographically smallest. 
Help him find such string or state that such string doesn't exist.

String *x* = *x*<sub class="lower-index">1</sub>*x*<sub class="lower-index">2</sub>... *x*<sub class="lower-index">*p*</sub> is lexicographically less than string *y* = *y*<sub class="lower-index">1</sub>*y*<sub class="lower-index">2</sub>... *y*<sub class="lower-index">*q*</sub>, if either *p* &lt; *q* and *x*<sub class="lower-index">1</sub> = *y*<sub class="lower-index">1</sub>, *x*<sub class="lower-index">2</sub> = *y*<sub class="lower-index">2</sub>, ... , *x*<sub class="lower-index">*p*</sub> = *y*<sub class="lower-index">*p*</sub>, or there is such number *r* (*r* &lt; *p*, *r* &lt; *q*), that *x*<sub class="lower-index">1</sub> = *y*<sub class="lower-index">1</sub>, *x*<sub class="lower-index">2</sub> = *y*<sub class="lower-index">2</sub>, ... , *x*<sub class="lower-index">*r*</sub> = *y*<sub class="lower-index">*r*</sub> and *x*<sub class="lower-index">*r* + 1</sub> &lt; *y*<sub class="lower-index">*r* + 1</sub>. The characters of the strings are compared by their ASCII codes.
A single line contains two positive integers *n* and *k* (1 ≤ *n* ≤ 10<sup class="upper-index">6</sup>, 1 ≤ *k* ≤ 26) — the string's length and the number of distinct letters.
print("_RANDOM_GUESS_1689419752.9487364")# 1689419752.9487572