In just a moment the hearts are gonna start flowing from bottom to top and the cookies are gonna start moving left and right and they seem to be somewhat synchronized with the music, perhaps based on trial and error by the student who implemented this one.

刚刚那一刻，那些爱心们从底部上浮到顶部,饼干人则向左向右移动,它们似乎都随着音乐的律动而变化着，也许这是那个制作该动画的同学,不断尝试的结果。

哈佛公开课 - 计算机科学课程节选

So it's a trial and error.

那么他反复尝试并得到错误答案。

哈佛公开课 - 计算机科学课程节选

You cannot resort to trial and error.

也就没法一个个试了

耶鲁公开课 - 基础物理课程节选