Problem

Given a list of strings items and a query string query, return all items whose text contains query as a case-insensitive substring. Preserve the original order of matching items. If query is an empty string, return all items.

Examples

Example 1:

Input: items = ["Apple", "banana", "Grape", "Pineapple"], query = "app"
Output: ["Apple", "Pineapple"]
Explanation: Both strings contain "app" when compared case-insensitively.

Example 2:

Input: items = ["Doc Viewer", "Search", "Insights", "Notebook"], query = "s"
Output: ["Search", "Insights"]
Explanation: Only these items contain the letter "s" or "S".

Constraints

• 1 <= len(items) <= 10^4
• 0 <= len(items[i]) <= 100
• 0 <= len(query) <= 100
• items[i] consists of printable characters