Add LongestCommonPrefix.java

Author: TheDarkW3b

src/main/java/com/thealgorithms/strings/LongestCommonPrefix.java

@@ -0,0 +1,17 @@
+package com.thealgorithms.strings;
+
+public final class LongestCommonPrefix {
+    public String longestCommonPrefix(String[] strs) {
+        if(strs == null || strs.length == 0) return "";
+
+        Arrays.sort(strs);
+        String shortest = strs[0];
+        String longest = strs[strs.length - 1];
+
+        int index = 0;
+        while(index < shortest.length() && index < longest.length() && shortest.charAt(index) == longest.charAt(index))
+            index++;
+
+        return shortest.substring(0, index);
+    }
+}