力扣1773(java&python)-统计匹配检索规则的物品数量（简单）

题目：

给你一个数组 items ，其中 items[i] = [typei, colori, namei] ，描述第 i 件物品的类型、颜色以及名称。

另给你一条由两个字符串 ruleKey 和 ruleValue 表示的检索规则。

如果第 i 件物品能满足下述条件之一，则认为该物品与给定的检索规则 匹配 ：

ruleKey == "type" 且 ruleValue == typei 。
ruleKey == "color" 且 ruleValue == colori 。
ruleKey == "name" 且 ruleValue == namei 。
统计并返回 匹配检索规则的物品数量 。

示例 1：

输入：items = [["phone","blue","pixel"],["computer","silver","lenovo"],["phone","gold","iphone"]], ruleKey = "color", ruleValue = "silver"
输出：1
解释：只有一件物品匹配检索规则，这件物品是 ["computer","silver","lenovo"] 。
示例 2：

输入：items = [["phone","blue","pixel"],["computer","silver","phone"],["phone","gold","iphone"]], ruleKey = "type", ruleValue = "phone"
输出：2
解释：只有两件物品匹配检索规则，这两件物品分别是 ["phone","blue","pixel"] 和 ["phone","gold","iphone"] 。注意，["computer","silver","phone"] 未匹配检索规则。
 

提示：

1 <= items.length <= 10⁴
1 <= typei.length, colori.length, namei.length, ruleValue.length <= 10
ruleKey 等于 "type"、"color" 或 "name"
所有字符串仅由小写字母组成

来源：力扣（LeetCode）
链接：https://leetcode.cn/problems/count-items-matching-a-rule
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解题思路：

模拟：由于需要由ruleKey来确定 ruleValue的下标，而ruleKey 只能为 "type"、"color" 或 "name"，故直接取ruleKey 的第一个字符来确定items中item的下标，遍历items数组，统计出item[i] == ruleValue的个数，进行返回。

java代码：

 1 class Solution {
 2     public int countMatches(List<List<String>> items, String ruleKey, String ruleValue) {
 3         int count = 0;
 4         int i = ruleKey.charAt(0) == 't'? 0 : (ruleKey.charAt(0) == 'c' ? 1 : 2);
 5         for(List<String> item : items){
 6             if(item.get(i).equals(ruleValue)){
 7                 count++;
 8             }
 9         }
10         return count;
11     }
12 }

 python3代码：

1 class Solution:
2     def countMatches(self, items: List[List[str]], ruleKey: str, ruleValue: str) -> int:
3         dic = {'type' : 0, 'color' : 1, 'name' : 2}
4         count = 0
5         for item in items:
6            if item[dic[ruleKey]] == ruleValue:
7                count += 1
8         return count