If you can figure out why fails on three letters instead of 12, you'll be more than half way to solving the problem.

如果你能明白为什么程序,在输入三个字母的单词的时候没法运行,你就已经解决了问题的一半了。

麻省理工公开课 - 计算机科学及编程导论课程节选

Yeah, there's like three letters there so that condition doesn't cause problems.

是哦，这里好像有三个字符,所以那个条件不会引起问题。

哈佛公开课 - 计算机科学课程节选

The first three letters of E. Coli are Eco, so Eco.

大肠杆菌的前三个字母是Eco,也就是酶名字中的Eco

耶鲁公开课 - 生物医学工程探索课程节选