2023-02-04 update: added "14. Longest Common Prefix"

README.md

@@ -12,8 +12,9 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 
 ### Easy
 
-| Name                 | Link to LeetCode                                         | Link to solution                          |
-|----------------------|----------------------------------------------------------|-------------------------------------------|
-| 1. Two Sum           | [Link](https://leetcode.com/problems/two-sum/)           | [Link](./lib/easy/two_sum.dart)           |
-| 9. Palindrome Number | [Link](https://leetcode.com/problems/palindrome-number/) | [Link](./lib/easy/palindrome_number.dart) |
-| 13. Roman to Integer | [Link](https://leetcode.com/problems/roman-to-integer/)  | [Link](./lib/easy/roman_to_integer.dart)  |
+| Name                      | Link to LeetCode                                             | Link to solution                              |
+|---------------------------|--------------------------------------------------------------|-----------------------------------------------|
+| 1. Two Sum                | [Link](https://leetcode.com/problems/two-sum/)               | [Link](./lib/easy/two_sum.dart)               |
+| 9. Palindrome Number      | [Link](https://leetcode.com/problems/palindrome-number/)     | [Link](./lib/easy/palindrome_number.dart)     |
+| 13. Roman to Integer      | [Link](https://leetcode.com/problems/roman-to-integer/)      | [Link](./lib/easy/roman_to_integer.dart)      |
+| 14. Longest Common Prefix | [Link](https://leetcode.com/problems/longest-common-prefix/) | [Link](./lib/easy/longest_common_prefix.dart) |

lib/easy/longest_common_prefix.dart

@@ -0,0 +1,28 @@
+// https://leetcode.com/problems/longest-common-prefix/
+class Solution {
+  String longestCommonPrefix(List<String> strs) {
+    if (strs.length == 1) {
+      return strs.first;
+    }
+    var result = '';
+    var first = strs.first;
+    var second = strs[1];
+    for (int i = 0; i < first.length && i < second.length; i++) {
+      if (first[i] == second[i]) {
+        result += first[i];
+      } else {
+        break;
+      }
+    }
+    if (result.isEmpty) {
+      return result;
+    }
+    for (int i = 2; i < strs.length; i++) {
+      var str = strs[i];
+      while (!str.startsWith(result)) {
+        result = result.substring(0, result.length - 1);
+      }
+    }
+    return result;
+  }
+}

test/easy/longest_common_prefix_test.dart

@@ -0,0 +1,29 @@
+import 'package:leetcode_dart/easy/longest_common_prefix.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group(
+    'Example tests',
+    () {
+      final lcp = Solution();
+      test(
+        'fl',
+        () => expect(
+          'fl',
+          lcp.longestCommonPrefix(
+            ["flower", "flow", "flight"],
+          ),
+        ),
+      );
+      test(
+        '',
+        () => expect(
+          '',
+          lcp.longestCommonPrefix(
+            ["dog", "racecar", "car"],
+          ),
+        ),
+      );
+    },
+  );
+}