Links of Problems
Problem 1 - https://codeforces.com/problemset/problem/1671/D
Problem 2 - https://codeforces.com/problemset/problem/1665/C
Problem 3 - https://codeforces.com/problemset/problem/1660/E
Problem 4 - https://codeforces.com/problemset/problem/1660/D
Time Stamp
0:00 Problem 1 - D. Insert a Progression
20:46 Problem 2 - C. Tree Infection
43:46 Problem 3 - E. Matrix and Shifts
01:03:46 Problems 4 - D. Maximum Product Strikes Back
