/**
 * @param {number} capacity
 */
var LRUCache = function(capacity) {
    this.capacity = capacity
    this.order = []
    this.map = {}
};

/**
 * @param {number} key
 * @return {number}
 */
LRUCache.prototype.get = function(key) {
    let existingItem = this.getItem(key)
    if (existingItem !== -1) {
        this.order.splice(this.order.indexOf(key), 1)
        this.order.push(key)
    }
    return existingItem
};

LRUCache.prototype.getItem = function(key) {
    if (this.map.hasOwnProperty(key)) {
        return this.map[key]
    } else {
        return -1
    }
};

/**
 * @param {number} key
 * @param {number} value
 * @return {void}
 */
LRUCache.prototype.put = function(key, value) {
    if (this.getItem(key) === -1) {
        if (this.order.length === this.capacity) {
            let keyToRemove = this.order.shift()
            delete this.map[keyToRemove]
        }
    } else {
        this.order.splice(this.order.indexOf(key), 1)
    }
    this.order.push(key)
    this.map[key] = value
};