Competitive Programming

My C++ practice solutions for Codeforces problems, along with a reusable contest template. Each solution is a standalone program with its own main() function.

Problem index

Problem links come from the local Competitive Programming Helper records. This is a practice archive; inclusion does not indicate a verified accepted submission.

Problem	Source
Good Contest	A_Good_Contest.cpp
Halloumi Boxes	A_Halloumi_Boxes.cpp
Line Trip	A_Line_Trip.cpp
Min Or Sum	A_Min_Or_Sum.cpp
Turn Into a Palindrome	A_Turn_Into_a_Palindrome.cpp
Before an Exam	B_Before_an_Exam.cpp
Fashionable Array	B_Fashionable_Array.cpp
The Eternal Immortality	B_The_Eternal_Immortality.cpp
Three Piles	B_Three_Piles.cpp
AND, OR, Sort!	C_AND_OR_Sort.cpp
GCD Treasury	C_GCD_Treasury.cpp

Compile and run

Use a GNU C++ compiler with C++17 support. The programs use the GCC header <bits/stdc++.h>.

Windows PowerShell, from this repository:

g++ -std=c++17 -O2 -Wall -Wextra A_Halloumi_Boxes.cpp -o solution.exe
.\solution.exe

Enter the problem's input after starting the program. To use a local input file:

Get-Content .\input.txt | .\solution.exe

Linux or macOS with GCC installed as g++:

g++ -std=c++17 -O2 -Wall -Wextra A_Halloumi_Boxes.cpp -o solution.out
./solution.out < input.txt

Compile one solution at a time. Compiling all files together would produce multiple definitions of main().

Template and local files

Copy Template.cpp when starting a new problem. Implement solve() and adjust whether main() reads a test-case count to match the problem's input format.

The .gitignore keeps compiled executables, build output, editor settings, CPH records, Test.cpp, and local input.txt / output.txt files out of Git. These files can still be used locally.

Save and upload new solutions

From this repository's folder:

git status
git add Your_New_Solution.cpp
git diff --cached
git commit -m "Add solution for problem name"
git push

• git status shows new, modified, and staged files.
• git add stages the file's current contents for the next commit. Run it again if you edit the file afterward.
• git diff --cached lets you review the staged changes.
• git commit records a snapshot in local history.
• git push uploads local commits to the configured GitHub branch.

Use git add . to stage all non-ignored changes in the current directory after reviewing git status.