LeetCode——Longest Substring Without Repeating Characters

public static int lengthOfLongestSubstring(String s) {
		//利用hash表
		HashMap<Character, Integer> map = new HashMap<Character, Integer>();
		int length = map.size();
		int lenTmp = map.size();
		char c[] = s.toCharArray();// 将字符串转换为字符数组
		int start = 0;
		
		for (int i = 0; i < c.length; i++) {
			if (map.containsKey(c[i])) {
				int j = start;
				while (c[j] != c[i]){
					map.remove(c[j]);
					j++;
				}
				map.remove(c[j]);
				start = j+1;
				map.put(c[i], i);
			} else {
				map.put(c[i], i);
			}
			lenTmp = map.size();
			length = (length < lenTmp) ? lenTmp : length;
		}
		return length;
	}