From d218fa111cd61a7efb07b0ea85e7214eca7559f9 Mon Sep 17 00:00:00 2001
From: Ki Rill <rillk500@gmail.com>
Date: Mon, 23 Dec 2019 16:23:51 +0600
Subject: [PATCH] Add files via upload

---
 lesson#7/main.d      |  36 ++++++++++++
 lesson#7/ticTacToe.d | 137 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 173 insertions(+)
 create mode 100644 lesson#7/main.d
 create mode 100644 lesson#7/ticTacToe.d

diff --git a/lesson#7/main.d b/lesson#7/main.d
new file mode 100644
index 0000000..291e207
--- /dev/null
+++ b/lesson#7/main.d
@@ -0,0 +1,36 @@
+//	Creating Tic Tac Toe (Noughts and Crosses) game
+//	LET'S LEARN: passing a variable by value and by reference
+
+import std.stdio: writeln;
+
+void main() {
+	int num = 100;
+
+	writeln("Step 1: num = ", num);
+
+	modify(num);
+
+	writeln("Step 3: num = ", num);
+}
+
+/*
+
+// passing by value 
+// when passing by value, a function copies the value of the variable to the argument of a function, and modifies the argument (the copy of that variable), 
+// not the original variable
+void modify(int argument) {
+	argument = 70;
+
+	writeln("Step 2: argument(num) = ", argument);
+}
+
+*/
+
+// passing by reference
+// when passing by reference, a fucntion copies the reference to the variable, and when modifying
+// the argument of a function, changes the actual value of the original variable
+void modify(ref int argument) {
+	argument = 70;
+
+	writeln("Step 2: argument(num) = ", argument);
+}
\ No newline at end of file
diff --git a/lesson#7/ticTacToe.d b/lesson#7/ticTacToe.d
new file mode 100644
index 0000000..a6a9180
--- /dev/null
+++ b/lesson#7/ticTacToe.d
@@ -0,0 +1,137 @@
+//	Creating Tic Tac Toe (Noughts and Crosses) game
+//	LET'S LEARN: passing a variable by value and by reference
+
+import std.stdio: writeln, write, readf, readln;
+import std.string: strip;
+
+void main() {
+	// game board
+	char[3][3] board = ' ';
+
+	// if true, player 1 makes a move, if false, player 2 makes a move
+	bool playerOneMove = true;
+
+	// mainMenu returns false if player decides to play, true if player exits
+	bool gameOver = mainMenu();
+	while(!gameOver) {
+		print(board);
+
+		// read X coordiante
+		int x = 0;
+		write("x:_");
+		readf(" %s", x);
+
+		// read Y coordinate
+		int y = 0;
+		write("y:_");
+		readf(" %s", y);
+
+		// if coordinates point to an empty slot, then make a move, otherwise, it is occupied by another piece
+		if(board[y][x] == ' ') {
+			if(playerOneMove) {
+				board[y][x] = 'x';
+			} else {
+				board[y][x] = 'o';
+			}
+
+			playerOneMove = !playerOneMove;
+		} else {
+			writeln();
+			writeln();
+			writeln("*************************************");
+			writeln("Position ", x, ", ", y, " is occupied! Try again.");
+			writeln("*************************************");
+		}
+
+		// checking whether the game is over
+		check(board, gameOver);
+	}
+
+	print(board);
+	if(playerOneMove) {
+		writeln("Player O won!");
+	} else {
+		writeln("Player X won!");
+	}
+	writeln("Thanks for playing!");
+}
+
+bool mainMenu() {
+	writeln("Hello! Welcome to Tic Tac Toe game!");
+	writeln("(1) Play");
+	writeln("(2) Exit");
+	write(":_");
+
+	string line = strip(readln());
+	if(line == "play" || line == "Play" || line == "1" || line == "p") { // if line = to either of these, then play, else, quit
+		return false;
+	}
+
+	return true;
+}
+
+// drawing the Tic Tac Toe game board
+void print(char[3][3] array) {
+	writeln();
+	writeln();
+
+	for(int i = 0; i < array.length; i++) {
+		write("\t", i);
+	}
+	writeln();
+
+	writeln("_ _ _ _ _ _ _ _ _ _ _ _ _ _");
+	for(int i  = 0; i < array.length; i++) {
+		write(i);
+		for(int j = 0; j < array[i].length; j++) {
+			write("   |   ", array[i][j]);
+		}
+		writeln();
+		writeln("_ _ _ _ _ _ _ _ _ _ _ _ _ _");
+	}
+
+	writeln();
+	writeln();
+}
+
+void check(char[3][3] array, ref bool gameOver) {
+	// checking if rows are Xs or Os
+	for(int i = 0; i < array.length; i++) {
+		if(array[i][0] != ' ' && array[i][1] != ' ' && array[i][2] != ' ') {
+			if(array[i][0] == array[i][1] && array[i][1] == array[i][2]) {
+				gameOver = true;
+			}
+		}
+	} 
+
+	// checking if colomns are Xs or Os
+	for(int i = 0; i < array.length; i++) {
+		if(array[0][i] != ' ' && array[1][i] != ' ' && array[2][i] != ' ') {
+			if(array[0][i] == array[1][i] && array[1][i] == array[2][i]) {
+				gameOver = true;
+			}
+		}
+	}
+
+	// checking if the diagonal slots starting from 0, 0 are Xs or Os
+	if(array[0][0] != ' ' && array[1][1] != ' ' && array[2][2] != ' ') {
+		if(array[0][0] == array[1][1] && array[1][1] == array[2][2]) {
+			gameOver = true;
+		}
+	}
+
+	// checking if the diagonal slots starting from 2, 0 are Xs or Os
+	if(array[2][0] != ' ' && array[1][1] != ' ' && array[0][2] != ' ') {
+		if(array[2][0] == array[1][1] && array[1][1] == array[0][2]) {
+			gameOver = true;
+		}
+	}
+}
+
+
+
+
+
+
+
+