### PROBLEM LINK:

**Author:** Akshay Venkataramani

**Tester:** Timothy

### DIFFICULTY:

CAKEWALK

### EXPLANATION:

All palindromes of length greater than 1 have characters that are repeated more than once. Hence, for all n > 1 the answer is -1. For n=1, the lexicographically smallest string of length 1 is ‘a’.

### AUTHOR’S SOLUTION:

Author’s solution can be found here.