description.md

Given two integer lists a and b of any length, return how many of the lists have 1 as their first element. The lists can be of any length, including empty.

For example:

• start1([1, 2, 3], [1, 3]) → 2
• start1([7, 2, 3], [1]) → 1
• start1([1, 2], []) → 1