Day12.2022.04.14

一、手写算法

https://leetcode-cn.com/problems/lru-cache/

思路

• 
  

  代码

  ```javascript /**
  • @param {number} capacity */ var LRUCache = function(capacity) { this.data = new Map(); this.max = capacity; };

/**

• @param {number} key
• @return {number} */ LRUCache.prototype.get = function(key) { if(this.data.has(key)){ let value = this.data.get(key); this.data.delete(key) this.put(key,value) return value }else{ return -1 }

};

/**

• @param {number} key
• @param {number} value
• @return {void} / LRUCache.prototype.put = function(key, value) { if(this.data.has(key)){ this.data.delete(key); } this.data.set(key,value); if(this.data.size > this.max){ this.data.delete(this.data.keys().next().value); } }; /*
• Your LRUCache object will be instantiated and called as such:
• var obj = new LRUCache(capacity)
• var param_1 = obj.get(key)
• obj.put(key,value) */ ```

  复杂度分析

• 时间复杂度：O(N)
• 空间复杂度：O(N)

二、编程题

//2.手写题：https://bigfrontend.dev/problem/implement-Promise-race

/**
 * @param {Array<Promise>} promises
 * @return {Promise}
 */
function race(promises) {
  // your code here
   if(promises.length === 0){
    return Promise.resolve([]);
  }
  return new Promise((resolve,reject)=>{
    let _promises = promises.map((promise)=>{
     promise.then(resolve,reject)
    })
  })
}