leetcode 387

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;
	}
}

  

原文地址:https://www.cnblogs.com/longlyseul/p/9879642.html