Problems

Very hard · Prime factorization · Number theory · Greedy algorithms · Combinatorics

Very easy · Implementation · Graphs

Medium · Strings

Medium · Geometry · Binary Search

Easy · Dynamic programming · Bitmasks

Easy · Graphs · Dynamic programming

Very easy · Greedy algorithms

Hard · Segment Tree · Range queries

Hard · Graphs · Constructive Algorithms

Very hard · Graphs · Dynamic programming

Very hard · Dynamic programming

Hard · Bitwise Operations · Greedy algorithms

Medium · Dynamic programming

Very easy · Dynamic programming

Medium · Dynamic programming · Knapsack · Sorting

Very hard · Graphs · Dynamic programming

Medium · Binary Search · Implementation

Hard · Graphs · Depth-first Search · Strings

Very hard · Geometry · Combinatorics

Very hard · Geometry

Very easy · Dynamic programming · String suffix structures

Very hard · Greedy algorithms · Trees · Dynamic programming · Schedules · Priority Queue

Medium · Brute force · Greedy algorithms

Easy · Trees

Medium · Bitmasks · Brute force