diff --git a/5.leetcode/src/com/fanxb/common/Q14.java b/5.leetcode/src/com/fanxb/common/Q14.java
new file mode 100644
index 0000000..f4851f4
--- /dev/null
+++ b/5.leetcode/src/com/fanxb/common/Q14.java
@@ -0,0 +1,47 @@
+package com.fanxb.common;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.stream.Stream;
+
+/**
+ * Created with IntelliJ IDEA
+ *
+ * @author fanxb
+ * Date: 2020/6/10 10:49
+ */
+public class Q14 {
+    public String longestCommonPrefix(String[] strs) {
+        if (strs.length == 1) return strs[0];
+        StringBuilder res = new StringBuilder();
+        int length = strs.length;
+        int minLength = Stream.of(strs).map(String::length).min(Integer::compare).orElse(0);
+        char a, b, c;
+        for (int i = 0; i < minLength; i++) {
+            for (int j = 1; j < length; j++) {
+                if (strs[j].charAt(i) != strs[j - 1].charAt(i)) return res.toString();
+            }
+            res.append(strs[0].charAt(i));
+        }
+        return res.toString();
+    }
+
+    public String longestCommonPrefix1(String[] strs) {
+        if (strs.length == 1) return strs[0];
+        String res = strs[0];
+        for (int i = 1; i < strs.length; i++) {
+            StringBuilder temp = new StringBuilder();
+            for (int j = 0; j < Math.min(res.length(), strs[i].length()); j++) {
+                if (res.charAt(j) == strs[i].charAt(j)) temp.append(res.charAt(j));
+                else break;
+            }
+            if (temp.isEmpty()) return "";
+            res = temp.toString();
+        }
+        return res;
+    }
+
+    public static void main(String[] args) {
+        Q14 instance = new Q14();
+    }
+}
diff --git a/5.leetcode/src/com/fanxb/common/Q151.java b/5.leetcode/src/com/fanxb/common/Q151.java
new file mode 100644
index 0000000..2623c3e
--- /dev/null
+++ b/5.leetcode/src/com/fanxb/common/Q151.java
@@ -0,0 +1,28 @@
+package com.fanxb.common;
+
+import java.util.Stack;
+
+public class Q151 {
+    public String reverseWords(String s) {
+        Stack<String> stack = new Stack<>();
+        StringBuilder temp = new StringBuilder();
+        for (int i = 0; i < s.length(); i++) {
+            if (s.charAt(i) == ' ') {
+                if (!temp.isEmpty()) {
+                    stack.push(temp.toString());
+                    temp = new StringBuilder();
+                }
+            } else {
+                temp.append(s.charAt(i));
+            }
+        }
+        if (!temp.isEmpty()) stack.push(temp.toString());
+        StringBuilder res = new StringBuilder();
+        res.append(stack.pop());
+        while (!stack.isEmpty()) res.append(" ").append(stack.pop());
+        return res.toString();
+    }
+
+    public static void main(String[] args) {
+    }
+}
diff --git a/5.leetcode/src/com/fanxb/common/Q6.java b/5.leetcode/src/com/fanxb/common/Q6.java
index 7501dea..59cc923 100644
--- a/5.leetcode/src/com/fanxb/common/Q6.java
+++ b/5.leetcode/src/com/fanxb/common/Q6.java
@@ -1,5 +1,7 @@
 package com.fanxb.common;
 
+import java.util.Arrays;
+
 public class Q6 {
     public String convert(String s, int numRows) {
         if (numRows == 1) {
@@ -39,7 +41,40 @@ public class Q6 {
         return new String(strs);
     }
 
+    public String convert1(String s, int numRows) {
+        int length = s.length();
+        if (length <= 1 || numRows == 1) return s;
+        int nSize = numRows * 2 - 2;
+        int lineNum = (numRows - 1) * (length / nSize + 1);
+        char[][] chars = new char[numRows][lineNum];
+        for (int i = 0; i < numRows; i++) Arrays.fill(chars[i], ' ');
+        int count = 0, m = 0, n = 0;
+        for (int i = 0; i < length; i++) {
+            chars[m][n] = s.charAt(i);
+            count++;
+            if (count == nSize) {
+                count = 0;
+                m--;
+                n++;
+            } else if (count < numRows) {
+                m++;
+            } else {
+                m--;
+                n++;
+            }
+        }
+        StringBuilder builder = new StringBuilder();
+        for (int i = 0; i < numRows; i++) {
+            for (int j = 0; j < lineNum; j++) {
+                if (chars[i][j] != ' ') {
+                    builder.append(chars[i][j]);
+                }
+            }
+        }
+        return builder.toString();
+    }
+
     public static void main(String[] args) {
-        System.out.println(new Q6().convert("PAYPALISHIRING", 4));
+        System.out.println(new Q6().convert1("PAYPALISHIRING", 4));
     }
 }