Create 014. Longest Common Prefix.java

Author: futurus

014. Longest Common Prefix.java

@@ -0,0 +1,38 @@
+// https://leetcode.com/problems/longest-common-prefix
+public class Solution {
+    public String longestCommonPrefix(String[] strs) {
+        if (strs.length == 0) return "";
+        else if (strs.length == 1) return strs[0];
+        else {
+            Arrays.sort(strs);
+    
+            String prefix = "";
+            for (int i = 0; i < strs[0].length(); i++) {
+                prefix = strs[0].substring(0, i+1);
+                System.out.println(prefix);
+                for (int s = 0; s < strs.length; s++) {
+                    if (!prefix.equals(strs[s].substring(0, i+1))) {
+                        return prefix.substring(0, prefix.length() - 1);
+                    }
+                }
+            }
+            
+            return prefix;
+        }
+    }
+}
+
+// reference
+// https://discuss.leetcode.com/topic/6987/java-code-with-13-lines
+
+public String longestCommonPrefix(String[] strs) {
+    if(strs == null || strs.length == 0)    return "";
+    String pre = strs[0];
+    int i = 1;
+    while(i < strs.length){
+        while(strs[i].indexOf(pre) != 0)
+            pre = pre.substring(0,pre.length()-1);
+        i++;
+    }
+    return pre;
+}