Count Items Matching a Rule

Problem Description

You are given an array items, where each items[i] = [type_i, color_i, name_i] describes the type, color, and name of the ith item. You are also given a rule represented by two strings, ruleKey and ruleValue. The ith item is said to match the rule if one of the following is true:

• ruleKey == "type" and ruleValue == type_i.
• ruleKey == "color" and ruleValue == color_i.
• ruleKey == "name" and ruleValue == name_i.

Return the number of items that match the given rule.

Key Insights

• The items are stored in a list of lists, where each inner list contains three strings.
• The condition for matching items depends on which attribute (type, color, or name) is being queried.
• A simple iteration through the items is sufficient to count the matches.

Space and Time Complexity

Time Complexity: O(n), where n is the number of items in the list. Space Complexity: O(1), since we are using a constant amount of extra space for counting.

Solution

To solve this problem, we will iterate through the items array and check each item's attribute against the provided ruleKey and ruleValue. We will use a simple conditional structure to determine which attribute to check based on the ruleKey. The counting will be done in a single pass through the list.

Code Solutions