Introduction:

1. https://cse.iitkgp.ac.in/~animeshm/generating_funct.pdf
2. zscoder blog 1
3. zscoder blog 2

To Read:

• https://codeforces.com/blog/entry/111120
• https://codeforces.com/blog/entry/112550
• https://codeforces.com/blog/entry/56422
• https://cf.nytdoj.com/blog/entry/99646