统计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 <= 1041 <= typei.length, colori.length, namei.length, ruleValue.length <= 10ruleKey 等于 "type"、"color" 或 "name"所有字符串仅由小写字母组成

var countMatches = function(items, ruleKey, ruleValue) {    let num = 0;    let map = new Map();    map = {        type : 0,        color: 1,        name: 2    }
    const index = map[ruleKey];    items.forEach((eles) => {        if (eles[index] === ruleValue) {            num++;        }    })    return num;};

/** * @param {string[][]} items * @param {string} ruleKey * @param {string} ruleValue * @return {number} */var countMatches = function(items, ruleKey, ruleValue) {    return items.filter(item =>item[{type: 0,color: 1,name: 2 }[ruleKey]] === ruleValue).length};