feat: 2025-10-28打卡

14.longest-common-prefix.java

@@ -0,0 +1,32 @@
+/*
+ * @lc app=leetcode id=14 lang=java
+ *
+ * [14] Longest Common Prefix
+ */
+
+// @lc code=start
+class Solution {
+    public String longestCommonPrefix(String[] strs) {
+        if(strs == null || strs.length == 0) {
+            return "";
+        }
+        String r = strs[0];
+        for(int i=1; i<strs.length;i++) {
+            r = longestCommonPrefix(r, strs[i]);
+        }
+        return r;
+    }
+
+    private String longestCommonPrefix(String a, String b) {
+        StringBuilder sb = new StringBuilder();
+        for(int i = 0; i<a.length() && i<b.length();i++) {
+            if(a.charAt(i) != b.charAt(i)) {
+                break;
+            }
+            sb.append(a.charAt(i));
+        }
+        return sb.toString();
+    }
+}
+// @lc code=end
+