题解 | #【模板】链表#

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void (async function () {
    // Write your code here
    let n = parseInt(await readline());
    let item = [];
    while (n--) {
        let line = await readline();
        let args = line.split(" ");
        switch (args[0]) {
            case "insert":
                if (!item.includes(args[1])) {
                    item.push(args[2]);
                } else {
                    item.splice(item.indexOf(args[1]), 0, args[2]);
                }
                break;
            case "delete":
                if (item.includes(args[1])) {
                    item.splice(item.indexOf(args[1]), 1);
                }
                break;
        }
    }
    if (item.length > 0) {
        console.log(item.join(" "));
    } else {
        console.log("NULL");
    }
})();

主要思路：数组模拟链表+javascript数组操作方法