Here is the list of some of the good tutorials written by codeforces users :-
C++
- C++ Tricks by HosseinYousefi
- C++ STL: map and set by adamant
- C++ STL: Policy based data structures by adamant
Data Structures
- Algorithm Gym :: Data Structures by PrinceOfPersia
- Everything about Segment Trees by PrinceOfPersia
- Efficient and easy Segtree by Al.Cash
- A simple introduction to "Segment tree beats" by jiry_2
- Sack(DSU on trees) by Arpa
- SQRT Tree by gepardo
- Link-Cut tree by adamant
DP
- DP on Trees by darkshadows
- SOS DP by usaxena95
- Recurrent Sequences — Application of combinatorics in DP by TooNewbie
- Non-trivial DP tricks & Techniques by zscoder
- Digit DP by flash_7
Math
- Invariants and monovariants by TooNewbie
- Mobius Inversion by Nisiyama_Suzune
- Dirichlet convolution by Nisiyama_Suzune
- Fast convolution for 64-bit integers by quasisphere
- Tutorial for FFT/NTT Part 1 by sidhant
- Tutorial for FFT/NTT Part 2 by sidhant
- On Fast Fourier Transform by adamant
- Extended Eratosthenes Sieve by lucyanna2018
- Burnside Lemma by flash_7
String Processing
- Z algorithm by paladin8
- Suffix Automata by quasisphere
- Transition between Z- and prefix functions by adamant
- Manacher's algorithm and code readability by adamant
Geometry
- Quaternion algebra and geometry by adamant
- Slope Trick by zscoder
- Nearest Neighbor Search by P_Nyagolov
- Convex Hull trick and Li chao tree by adamant
- Geometry: 2D points and lines by Al.Cash
- Geometry: Polygon algorithms by Al.Cash
Graphs
- 0-1 BFS by himanshujaju
- 2-SAT by HosseinYousefi
- Algorithm Gym :: Graph Algorithms by PrinceOfPersia
Others
- Parallel Binary Search by himanshujaju
- General ideas and tricks by adamant
If you know some good tutorial on codeforces which is not in this list and another list provided below please mention it in the comments I will add that in the list.
Another Similar List
Good Blog Post Resources about Algorithm and Data Structures