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.
Code (Java):
class Solution { public int firstUniqChar(String s) { if (s == null || s.length() == 0) { return -1; } int[] counts = new int[26]; for (int i = 0; i < s.length(); i++) { char c = s.charAt(i); counts[c - 'a']++; } for (int i = 0; i < s.length(); i++) { char c = s.charAt(i); if (counts[c - 'a'] == 1) { return i; } } return -1; } }
No comments:
Post a Comment