Merge branch 'treap'

main.cpp

@@ -4,6 +4,8 @@
 #include <vector>
 #include <fstream>
 
+#include "treap.hpp"
+
 using std::string;
 using std::vector;
 
@@ -12,16 +14,16 @@ enum mode_type { insert, normal };
 
 
 // Global variables
-vector<string> file(0);
+treap file;
 int row = 0, col = 0;
 
 // Accessing the file
-char get(int r, int s) { return file[r][s]; }
+string get_line(int r) { return file.find(r)->text; }
-void set(int r, int s, char ch) { file[r][s] = ch; }
+char get(int r, int s) { return get_line(r)[s]; }
-void insert_char(int r, int s, char ch) { file[r].insert(s, string{ch}); }
+void set(int r, int s, char ch) { file.find(r)->text[s] = ch; }
-string get_line(int r) { return file[r]; }
+void add_line(int r, string text = "") { file.insert(r, text); }
-void add_line(int r) { file.insert(file.begin() + r, ""); }
+void remove_line(int r) { file.remove(r); }
-void remove_line(int r) { file.erase(file.begin() + r); }
+void insert_char(int r, int s, char ch) { file.find(r)->text.insert(s, string{ch}); }
 
 // For normal mode not to write to terminal
 void step_back() {
@@ -37,9 +39,10 @@ bool load(string filename) {
 	std::ifstream infile(filename);
 	if(!infile.good())
 		return 1;
+
 	string line;
 	while (std::getline(infile, line))
-		file.push_back(line);
+		file.insert(file.size(), line);
 	return 0;
 }
 
@@ -48,8 +51,8 @@ bool save(string filename) {
 	std::ofstream outfile(filename);
 	if(!outfile.good())
 		return 1;
-	for(string line : file)
+	for(int i = 0; i < file.size(); ++i)
-		outfile << line << std::endl;
+		outfile << get_line(i) << std::endl;
 	return 0;
 }
 
@@ -58,7 +61,7 @@ void print_file() {
 	clear();
 	for(int i = 0; i < file.size(); i++) {
 		move(i, 0);
-		adds(file[i]);
+		adds(get_line(i));
 	}
 	move(row, col);
 }
@@ -110,7 +113,7 @@ void move_cursor(char ch) {
 			break;
 
 		case 'l':
-			if(col < file[row].size())
+			if(col < get_line(row).size())
 				move(row, ++col);
 			break;
 	}

treap.hpp

@@ -0,0 +1,115 @@
+#include <string>
+#include <cstdlib>
+#include <utility>
+
+using std::string;
+typedef unsigned long long count_type;
+
+// Treap node representation of a line
+struct line {
+	count_type priority, size;
+	string text;
+	line *left, *right;
+
+	line(count_type _p, string _t) : priority(_p), text(_t), size(1), left(nullptr), right(nullptr) {}
+};
+typedef std::pair<line*, line*> two_lines;
+
+// Treap representation of a file
+class treap {
+	line* root;
+
+	// Get size uf a subtreap
+	int get_size(line* l) {
+		if(l == nullptr) return 0;
+		return l->size;
+	}
+
+	// Split treap by k-th element
+	// Hopefully with sizes
+	two_lines split(line *l, count_type k) {
+		if(l == nullptr) return {nullptr, nullptr};
+
+		if(get_size(l->left) >= k) {
+			// In the left subtree
+			auto two = split(l->left, k);
+			l->left = two.second;
+			l->size -= get_size(two.first);
+			return {two.first, l};
+		}
+		else {
+			// In the right subtree
+			auto two = split(l->right, k - (1+get_size(l->left)));
+			l->right = two.first;
+			l->size -= get_size(two.second);
+			return {l, two.second};
+		}
+	}
+
+	// Join two treaps
+	// Hopefully with working sizes
+	line* join(line *a, line *b) {
+		if(a == nullptr) return b;
+		if(b == nullptr) return a;
+
+		if(a->priority < b->priority) {
+			a->size += get_size(b);
+			a->right = join(a->right, b);
+			return a;
+		}
+		else {
+			b->size += get_size(a);
+			b->left = join(a, b->left);
+			return b;
+		}
+	}
+	line* join(two_lines two) { return join(two.first, two.second); }
+
+	// Find k-th line of file
+	line* find(line* l, count_type k) {
+		if(l == nullptr) return nullptr;
+
+		if(k <= get_size(l->left))
+			return find(l->left, k);
+		else if(k == get_size(l->left)+1)
+			return l;
+		else
+			return find(l->right, k - (1+get_size(l->left)) );
+	}
+
+public:
+	treap() {
+		srand(120);
+		root = nullptr;
+	}
+	// File access
+	line* find(count_type k) {
+		if(k >= root->size)
+			return nullptr;
+		// Don't find index k, but k-th line -> +1
+		return find(root, k+1);
+	}
+
+	// Line insert
+	void insert(int k, string s) {
+		line *l = new line(rand(), s);
+
+		if(root == nullptr) {
+			root = l;
+			return;
+		}
+
+		auto two = split(root, k);
+		two.first = join(two.first, l);
+		root = join(two);
+	}
+	// Line removal
+	void remove(count_type k) {
+		auto two = split(root, k+1);
+		two.first = split(two.first, k).first;
+		root = join(two);
+	}
+	count_type size() {
+		return get_size(root);
+	}
+};