diff --git a/src/main/java/com/leetcode/strings/LongestCommonPrefix.java b/src/main/java/com/leetcode/strings/LongestCommonPrefix.java
index 07bd6392..9e97d6b4 100644
--- a/src/main/java/com/leetcode/strings/LongestCommonPrefix.java
+++ b/src/main/java/com/leetcode/strings/LongestCommonPrefix.java
@@ -39,10 +39,15 @@ public static String longestCommonPrefix(String[] strs) {
     }
 
     public static void main(String[] args) {
-        System.out.println(longestCommonPrefix(new String[]{}));
-        System.out.println(longestCommonPrefix(new String[]{""}));
-        System.out.println(longestCommonPrefix(new String[]{"a"}));
-        System.out.println(longestCommonPrefix(new String[]{"flower", "flow", "flight"}));
-        System.out.println(longestCommonPrefix(new String[]{"dog", "racecar", "car"}));
+        assertEquals("", longestCommonPrefix(new String[]{""}));
+        assertEquals("a", longestCommonPrefix(new String[]{"a"}));
+        assertEquals("abcd", longestCommonPrefix(new String[]{"abcdefg", "abcdgfe", "abcdsafa", "abcdewfad",
+        "abcdacx", "abcdplp", "abcddmm", "abcdmms", "abcdsafa", "abcdwczsace", "abcdwfacesd", "abcdqwrq",
+        "abcdeas", "abcdascadsa", "abcdqsxz", "abcdbc", "abcdavs", "abcdpmsadsa", "abcdsaca", "abcdbww",
+        "abcdwqsax", "abcdasfe", "abcdaer"}));
+        assertEquals("abcdefghijklmnopqrstuvwxyz",
+        longestCommonPrefix(new String[]{
+        "abcdefghijklmnopqrstuvwxyzafwfafaafqfwafafadafeaaffadacesgrbrfseesfegwafeagewzfafafsa",
+        "abcdefghijklmnopqrstuvwxyzwasfdafsaawfdwafagafagagsgfsafsgdsdfdafafsafafadafaf"}));
     }
 }