编辑代码

async function main() {
    setTimeout(() => {
        console.log(1)
    }, 0)

    async function timeout() {
        const a = await new Promise((res, rej) => {
            setTimeout(() => {
                console.log(2)
                res(3)
            }, 0)
        })
        console.log(a)
    }

    await timeout()

    console.log(4)
}

main()