Starting work on #7.

2022/7/Makefile

@@ -0,0 +1 @@
+../starter/Makefile

2022/7/main.cpp

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+#include <algorithm>
+#include <fstream>
+#include <iostream>
+#include <set>
+#include <stack>
+#include <string>
+#include <vector>
+
+std::vector<std::string> SplitStr(std::string str, const std::string &delim)
+{
+	std::vector<std::string> rtn;
+
+	for(auto split = str.find(delim); split != std::string::npos; split = str.find(delim))
+	{
+		rtn.push_back(str.substr(0, split));
+		str = str.substr(split + delim.size()); // chop off beginning
+	}
+	if(str.size())
+		rtn.push_back(str);
+
+	return rtn;
+}
+
+class File {
+public:
+	File(const std::string &set_filename, unsigned long set_size)
+		{
+			this->size = set_size;
+			this->filename = set_filename;
+		}
+
+	virtual ~File()
+		{
+		}
+
+	const std::string& Filename() const
+		{
+			return filename;
+		}
+	virtual unsigned long Size() const
+		{
+			return size;
+		}
+
+protected:
+	unsigned long size;
+	std::string filename;
+};
+
+class Folder : public File {
+public:
+	Folder(const std::string &filename)
+		: File(filename, 0)
+		{
+		}
+
+	unsigned long Size() const override
+		{
+			unsigned long size = 0;
+			for(const auto *file : files)
+				size += file->Size();
+			return size;
+		}
+
+	void AddFile(const std::string &filename,
+	             unsigned long size)
+		{
+			// make sure the file doesn't already exist:
+			if(std::find_if(files.begin(), files.end(),
+			                [&](const File *file) {
+				                return file->Filename() == filename;
+			                }) != files.end())
+			{
+				std::cerr << "Folder \"" << this->Filename() << "\" already contains "
+				          << "the file \"" << filename << "\"." << std::endl;
+				exit(-1);
+			}
+
+			// increment this folder's size total:
+			this->size += size;
+
+			// add the file:
+			files.push_back(new File(filename, size));
+		}
+
+	void AddFolder(const std::string &name)
+		{
+			if(std::find_if(files.begin(), files.end(),
+			                [&](const File *file) {
+				                return file->Filename() == name;
+			                }) != files.end())
+			{
+				std::cout << "NOTE: Folder \"" << this->Filename() << "\" already contains "
+				          << "the subfolder \"" << name << "\"." << std::endl;
+				// exit(-1);
+			}
+
+			files.push_back(new Folder(name));
+		}
+
+	const std::vector<File*>& Files() const
+		{
+			return files;
+		}
+
+private:
+	std::vector<File*> files;
+};
+
+int main()
+{
+	std::ifstream ifs("data.txt");
+	if(!ifs.is_open())
+	{
+		std::cerr << "Missing data.txt." << std::endl;
+		return -1;
+	}
+
+	Folder root("/");
+	std::stack<Folder*> dir_stack;
+	dir_stack.push(&root);
+
+	for(std::string line; std::getline(ifs, line); )
+	{
+		if(line == "")
+			continue;
+
+		if(line.starts_with("$ ls"))
+			continue;
+		else if(line.starts_with("$ cd"))
+		{
+			auto to = line.substr(5);
+			if(to == "/")
+			{
+				while(dir_stack.size() > 1)
+					dir_stack.pop();
+			}
+			else if(to == "..")
+			{
+				if(dir_stack.size() > 1)
+					dir_stack.pop();
+			}
+			else
+			{
+				auto existing = std::find_if(dir_stack.top()->Files().begin(),
+			                     dir_stack.top()->Files().end(),
+			                     [&to](const File *f){
+				                     return f->Filename() == to;
+			                     });
+				if(existing != dir_stack.top()->Files().end()) // found!
+				{
+					// Check to see if it's a folder, first:
+					Folder *folder = dynamic_cast<Folder*>(*existing);
+					if(folder)
+						dir_stack.push(folder);
+					else
+					{
+						std::cerr << (*existing)->Filename() << " is a file, not a folder."
+						          << std::endl;
+						exit(-3);
+					}
+				}
+				else
+					std::cerr << "could not navigate to \"" << to << "\" from \""
+					          << dir_stack.top()->Filename() << "\"." << std::endl;
+			}
+		}
+		else if(line.starts_with("dir "))
+		{
+			dir_stack.top()->AddFolder(line.substr(4));
+		}
+		else
+		{
+			auto values = SplitStr(line, " ");
+			dir_stack.top()->AddFile(values[1], std::atol(values[0].c_str()));
+		}
+	}
+
+	return 0;
+}