LeetCode 387 First Unique Character in a String

Given a string, find the first non-repeating character in it and return it's index. If it doesn't exist, return -1.

Examples:

s = "leetcode"return 0.s = "loveleetcode",return 2.

Note: You may assume the string contain only lowercase letters.

Runtime: 16 ms

public int firstUniqChar(String s) {int[] count = new int[26];char[] chars = s.toCharArray();for (int i = 0; i < chars.length; i++)count[chars[i] - 'a']++;for (int i = 0; i < chars.length; i++)if (count[chars[i] - 'a'] == 1) return i;return -1;}