第38题 （头条）异步笔试题

请写出下面代码的运行结果

    async function async1() {
        console.log('async1 start');
        await async2();
        console.log('async1 end');
    }
    async function async2() {
        console.log('async2');
    }
    console.log('script start');
    setTimeout(function() {
        console.log('setTimeout');
    }, 0)
    async1();
    new Promise(function(resolve) {
        console.log('promise1');
        resolve();
    }).then(function() {
        console.log('promise2');
    });
    console.log('script end');

    // script start 
    // async1 start
    // async2 
    // promise1
    // script end
    // async1 end
    // promise2
    // setTimeout