- Library is imported from solutions for 2017.
- Walking on grid with field.Step4.
- Walking on grid filled by field.FillFromString.
- Simple triangle check.
- sort.Stable. Btw, it's internals are worth checking.
- crypto/md5.Sum.
- No need to convert hash to string to check zeroes.
- Optimize: no need to use strconv.Itoa either.
- Generic Frequency map should come in handy. This was fastest solved task in year 2016 (top100 - 375s), due to some languages have library functions to get most frequent and least frequent value in set.
- Search for ABBA-type substrings, ABA and BAB-type correlations.