Update 3-paths.js

Author: Ayogit1

Sprint-1/1-key-exercises/3-paths.js

@@ -17,7 +17,7 @@ console.log(`The base part of ${filePath} is ${base}`);
 // Create a variable to store the dir part of the filePath variable
 // Create a variable to store the ext part of the variable
 
-const dir = filePath.substring(0, 44);
+const dir = filePath.substring(0, lastSlashIndex);
 console.log(`The dir part of the filePath variable is  ${dir}`);
 const lastDotIndex = filePath.lastIndexOf(".");
 const ext = filePath.slice(lastDotIndex + 1);