[Leet Code] Count Items Matching a Rule
2 min readMar 20, 2021
Leet Code: https://leetcode.com/problems/count-items-matching-a-rule/
Problem:
You are given an array items
, where each items[i] = [typei, colori, namei]
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"
andruleValue == typei
.ruleKey == "color"
andruleValue == colori
.ruleKey == "name"
andruleValue == namei
.
Return the number of items that match the given rule.
Example 1:
Input: items = [["phone","blue","pixel"],["computer","silver","lenovo"],["phone","gold","iphone"]], ruleKey = "color", ruleValue = "silver"
Output: 1
Explanation: There is only one item matching the given rule, which is ["computer","silver","lenovo"].
Example 2:
Input: items = [["phone","blue","pixel"],["computer","silver","phone"],["phone","gold","iphone"]], ruleKey = "type", ruleValue = "phone"
Output: 2
Explanation: There are only two items matching the given rule, which are ["phone","blue","pixel"] and ["phone","gold","iphone"]. Note that the item ["computer","silver","phone"] does not match.
Constraints:
1 <= items.length <= 104
1 <= typei.length, colori.length, namei.length, ruleValue.length <= 10
ruleKey
is equal to either"type"
,"color"
, or"name"
.- All strings consist only of lowercase letters.
Solution:
class Solution(object):
def countMatches(self, items, ruleKey, ruleValue):
"""
:type items: List[List[str]]
:type ruleKey: str
:type ruleValue: str
:rtype: int
"""
dictionary = {"type": 0, "color": 1, "name" : 2}
indexPos = dictionary[ruleKey]
answer = 0
for i,v in enumerate(items):
if v[indexPos] == ruleValue:
answer += 1
return answer