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.
给定一个字符串,查找其中的第一个非重复字符并返回其索引。如果它不存在,返回-1。
例子:
s =“leetcode”
返回0。
s =“loveleetcode”,
返回2。
class Solution { public int firstUniqChar(String s) { int result = -1; HashMap<Character, Integer> hm1 = new HashMap<Character, Integer>(); for (char c : s.toCharArray()) { if (hm1.containsKey(c)) { hm1.put(c, hm1.get(c) + 1); } else { hm1.put(c, 1); } } for (int count = 0; count < s.length(); count++) { if (hm1.get(s.charAt(count)) == 1) { result = count; break; } } return result; } }