JiwoonKim / algorithm-pie

solutions to algorithm pie problems

algorithm-pie 🍮

collection of common algorithm problems

https://www.geeksforgeeks.org/top-algorithms-and-data-structures-for-competitive-programming/#algo4

🔧 Useful Mechanisms To Remember

list of useful mechanisms (functions) to remember

1. Sorting

2. Searching

3. Greedy Algorithm

4. Dynamic Programming

5. Backtracking

a method of brute-force search (a.k.a exhaustive search)

• permutation
• n queen problem
• sudoku

6. Graph Algorithms

7. Math and Logic Puzzles

+ Permutations

1. how to create next permutation (7(1)-1. next permutation)
2. figure out k-th permutation
3. create all permutations (7(1)-3. permutations 🔥)
   • use backtracking to swap values in N-for-N loops
   • use STL next_permutation() or for convenience (sort prior to using)
4. create nPk permutations (7(1)-2. nPk permutations 🔥)
   • use backtracking to build up to k-length permutations
5. use backtracking to create all lengthed permutations (7(1)-5. all length permutations 🔥)
   • nP1 + nP2 + ... + nPn-1 + nPn
   • use backtracking to build up k-length permutations

+ Combinations

1. (7(2)-1. combinations 🔥)
2. (7(2)-2. all length combinations 🔥)
3. use no count + counting principle to count number of all possible length combinations (7(2)-3. count all combinations 🚀)

• primality test
• euclid algorithm
• Find kth Permutation
• Integer Division
• Pythagorean Triplets
• All Sum Combinations
• Find Missing Number
• Permute String
• All Subsets
• Is Number Valid?
• Power of a Number
• Calculate Square Root