资料提炼：共收集到符合上述要求的文献62篇，排除28篇重复性研究。34篇符合纳入标准。

DATA EXTRACTION: There were 62 literatures in accordance with the criteria, 28 repeated ones were excluded, and 34 articles met the inclusion criteria.

youdao

资料提炼：共收集30篇文献，排除14篇重复性研究，其余16篇查找全文并进行综述。

DATA EXTRACTION: Totally 30 articles were collected, and 14 ones were excluded due to repetitive study. The full-texts of other 16 articles were searched and summarized.

youdao

资料提炼：共收集到符合上述要求的文献40篇，排除27篇重复性研究，13篇符合纳入标准。

DATA EXTRACTION: There were 40 literatures in accordance with the above criteria, 27 repetitive studies were excluded, and 13 were accorded with the inclusive criteria.

youdao

You're not going to start for the rest of your life if you ever need to solve a problem with a computer from scratch, odds are you're going to reach for some off the shelf packages or libraries or tools that other people wrote so that people like us don't have to reinvent the wheel again and again.

如果你想用Scratch来解决问题,却使用其他人写的程序,或者利用现成的资料或工具,这样以来,我们的确可以避免做重复性的工作,但却永远学不会编程。

哈佛公开课 - 计算机科学课程节选