algorithm004-01 · miaoswen · Dec 15, 2019
diff --git a/Week 08/id_321/LeetCode_151_321.java b/Week 08/id_321/LeetCode_151_321.java
@@ -0,0 +1,25 @@
+package week08;
+
+public class Solution151 {
+
+	class Solution {
+		public String reverseWords(String s) {
+			StringBuffer res = new StringBuffer();
+			s = s.trim();
+			int i = s.length() - 1, j = s.length();
+			while (i > 0) {
+				if (s.charAt(i) == ' ') {
+					res.append(s.substring(i + 1, j));
+					res.append(' ');
+					while (s.charAt(i) == ' ') {
+						i--;
+					}
+					j = i + 1;
+				}
+				i--;
+			}
+			return res.append(s.substring(0, j)).toString();
+		}
+	}
+
+}
diff --git a/Week 08/id_321/LeetCode_205_321.java b/Week 08/id_321/LeetCode_205_321.java
@@ -0,0 +1,19 @@
+package week08;
+
+public class Solution205 {
+
+	class Solution {
+		public boolean isIsomorphic(String s, String t) {
+			char[] ch1 = s.toCharArray();
+			char[] ch2 = t.toCharArray();
+			int len = s.length();
+			for (int i = 0; i < len; i++) {
+				if (s.indexOf(ch1[i]) != t.indexOf(ch2[i])) {
+					return false;
+				}
+			}
+			return true;
+		}
+	}
+
+}
diff --git a/Week 08/id_321/LeetCode_387_321.java b/Week 08/id_321/LeetCode_387_321.java
@@ -0,0 +1,37 @@
+package week08;
+
+import java.util.HashMap;
+
+public class Solution387 {
+
+	public int firstUniqChar(String s) {
+
+		int array[] = new int[26];
+		for (char ch : s.toCharArray()) {
+			array[ch - 'a']++;
+		}
+		for (int i = 0; i < s.length(); i++) {
+			if (array[s.charAt(i) - 'a'] == 1) {
+				return i;
+			}
+		}
+		return -1;
+	}
+
+	public int firstUniqChar2(String s) {
+		HashMap<Character, Integer> count = new HashMap<Character, Integer>();
+		int n = s.length();
+
+		for (int i = 0; i < n; i++) {
+			char c = s.charAt(i);
+			count.put(c, count.getOrDefault(c, 0) + 1);
+		}
+
+		for (int i = 0; i < n; i++) {
+			if (count.get(s.charAt(i)) == 1)
+				return i;
+		}
+		return -1;
+	}
+
+}
diff --git a/Week 08/id_321/LeetCode_680_321.java b/Week 08/id_321/LeetCode_680_321.java
@@ -0,0 +1,29 @@
+package week08;
+
+public class Solution680 {
+//��������ָ�룬�ж����������Ƿ���� ������ʱ �������һ���ַ������ұ�����һ���ַ���ֻ������һ��
+	public boolean validPalindrome(String s) {
+		int left = 0;
+		int right = s.length() - 1;// "abca"
+		while (left < right) {// ����������left=right��ʱ��
+
+			if (s.charAt(left) != s.charAt(right)) {
+				return isPalindrome(s, left, right - 1) || isPalindrome(s, left + 1, right);
+			}
+			// �������ߵ��ַ���ȡ�
+			left++;
+			right--;
+		}
+		return true;
+	}
+
+	private boolean isPalindrome(String s, int i, int j) {
+		while (i < j) {
+			if (s.charAt(i++) != s.charAt(j--)) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+}
diff --git a/Week 08/id_321/LeetCode_72_321.java b/Week 08/id_321/LeetCode_72_321.java
@@ -0,0 +1,29 @@
+package week08;
+
+public class Solution72 {
+
+	public int minDistance(String word1, String word2) {
+
+		int len1 = word1.length();
+		int len2 = word2.length();
+		int[][] dp = new int[len1 + 1][len2 + 1];
+
+		for (int i = 1; i <= len2; i++) {
+			dp[0][i] = dp[0][i - 1] + 1;
+		}
+		for (int j = 1; j <= len1; j++) {
+			dp[j][0] = dp[j - 1][0] + 1;
+		}
+		for (int i = 1; i <= len1; i++) {
+			for (int j = 1; j <= len2; j++) {
+				if (word1.charAt(i - 1) == word2.charAt(j - 1)) {
+					dp[i][j] = dp[i - 1][j - 1];
+				} else {
+					dp[i][j] = Math.min(Math.min(dp[i - 1][j], dp[i][j - 1]), dp[i - 1][j - 1]) + 1;
+				}
+			}
+		}
+		return dp[len1][len2];
+
+	}
+}