Amazon Web Services is experimenting with optimizing search queries based on the location of the first unique character in a search. You have been asked to help test the query your team has created to ensure it works as designed. A unique character is one which appears only once in a string. Given a string consisting of lowercase English letters only, return the index of the first occurrence of a unique character in the string using 1-based indexing. If the string does not contain any unique character, return -1.
Function Description
Complete the function findFirstUnique
in the editor below.
findFirstUnique
has the following parameter(s):
string s
: a string
Returns
int
: either the 1-based index or -1
Example 1:
Input: s = "statistics"
Output: 3
Explanation:The unique characters are [a, c] among which a occurs first. Using 1-based indexing, it is at index 3.
1 <= len of s <= 105
The string s consists of lowercase English letters only.


input:
output: