updated readme, and fixed linux compilation

.gitignore

@@ -3,3 +3,4 @@ tests
 tmp
 .DS_Store
 .idea
+*.dat

README.md

@@ -0,0 +1,39 @@
+# External Merge Sort (Big Buffer Strategy)
+A C++20 implementation of an external sorting algorithm designed to sort files that are too large to fit into the system's RAM. This project uses a Big Buffer approach to minimize disk I/O by maximizing the use of available memory during both the initial run creation and the merging phases.
+
+# Requirements
+  Clang++ or G++ (Support for C++20 required)
+  Make
+  
+# Compilation
+```bash
+make
+````
+
+# Usage
+
+The binary is located in the build/ directory after compilation.
+
+# Generate Data
+
+# To generate a test file with 100,000 random records:
+```bash
+./build/main -g 100000 -o input.dat
+```
+
+# Sort Data
+
+To sort the generated file using 11 buffers of 10 records each:
+```bash
+./build/main -i input.dat -o output.dat -n 11 -b 10
+```
+
+# Options
+Flag	Description
+-i	Input file path
+-o	Output file path
+-n	Number of buffers (minimum 3)
+-b	Size of each buffer (number of records)
+-g	Generate count random records
+-e	Evaluate and print the contents of a file
+-d	Temporary directory for merge runs

include/file_reader.hpp

@@ -1,4 +1,5 @@
 #pragma once
+#include <vector>
 #include "record.hpp"
 #include <fstream>
 #include <optional>

include/file_writer.hpp

@@ -1,4 +1,6 @@
 #pragma once
+#include <vector>
+#include <filesystem>
 #include "record.hpp"
 #include <fstream>
 #include <span>

makefile

@@ -1,4 +1,4 @@
-CXX = clang++
+CXX = g++
 CXXFLAGS = -g -std=c++20 -Iinclude -Wall -Wextra -Werror
 LDFLAGS =
 

src/file_reader.cpp

@@ -1,3 +1,4 @@
+#include <vector>
 #include "../include/file_reader.hpp"
 
 void FileReader::refill_buffer()

src/file_writer.cpp

@@ -1,3 +1,4 @@
+#include <vector>
 #include "../include/file_writer.hpp"
 
 void FileWriter::write_buffer()

src/merge_sorter.cpp

@@ -1,3 +1,5 @@
+#include <algorithm>
+#include <queue>
 #include "../include/merge_sorter.hpp"
 
 std::span<Record> MergeSorter::get_chunk_span(size_t chunk_index)