shafaet / programming-contest-algorithms

Problem Solving in Online Judge

This repository contains some frequently used algorithms for competitive programming.

Author: Shafaet Ashraf [email protected]

BASIC SUBROUTINES

Graph

DFS cycle finding

• SPOJ Paradox

Max Flow

• POJ 3204- Ikki's Story I - Road Reconstruction

Min Cost Max Flow

• UVA 12092 - Paint the Roads

Bipartite Matching(Konigs Theorem)

• UVA 11419 - Sam i am

Prufer Codes

• Timus 1069 Prufer Code

Strongly Connected components

• Topcoder - BikeRiding(SRM 545 div2 level 3)

Bridge

• UVA 1310 (One way traffic)

Dynamic Programming

Knuth Optimization

• UVA 10304-Optimal Binary Search Tree
• ZOJ 2860 Breaking Strings
• Andrew-Stankevich-10C-Order Preserving Codes

Convex Hull Optimization

• APIO10-commandos
• USACO-MAR08-ACQUIRE

LCS Variants

• Light OJ 1110 - An Easy LCS (Printing Lexicographically Smallest LCS)
• Light OJ 1157 - LCS Revisited (Number of Unique LCS)

Data Structure

Heavy Light Decomposition

• Timus 1553 Caves and Tunnels
• UVA 12424 Answering Queries On A Tree

RMQ using Sparse Table

• POJ 2019 USACO-Cornfield

Balanced Binary Search Tree(TREAP)

• SPOJ QMAX3VN

2D Binary Indexed Tree

• LightOJ 1266 - Points in Rectangle

2D Segment Tree

• UVA 11297 Census

Lowest Common Ancestor Using Sparse Table*

• LightOJ 1162 - Min Max Roads

Matrix Exponentiation

• SPOJ SNAKYNUM
• LightOJ 1268 - Unlucky String

Geometry

Max Co-linear Points

• Timus 1052 Rabbit Hunt

Point Segment Distance (3D)

• LightOJ 1240 - Point Segment Distance (3D)

String Algorithms

KMP

• LightOJ 1268 - Unlucky String

Gaussian Elimination

Bitwise Gaussian Elimination over gf2

• UVALIVE 5070 Awkward Lights

Others

Permutation with k non-fixed points

• LightOJ 1095 - Arrange The Numbers

Prime factorization inside sieve of eratosthenes

• UVALIVE 4735- Not So Flat After All

Longest Increasing Subsequence in O(nlogk)

• UVA 11031 - Looking for a Subset

Ternary Search

• LightOJ 1240 - Point Segment Distance (3D)

2D Grid Compression

• UVA 11918 - Traveler of Gridland
• UVA 12069 - Robots inside the Labyrinth