diff --git a/appC/.gitignore b/appC/.gitignore
new file mode 100644
index 0000000..0ddaba1
--- /dev/null
+++ b/appC/.gitignore
@@ -0,0 +1,2 @@
+/bin/*.exe
+/build/*.o
\ No newline at end of file
diff --git a/appC/.vscode/launch.json b/appC/.vscode/launch.json
new file mode 100644
index 0000000..d26b9de
--- /dev/null
+++ b/appC/.vscode/launch.json
@@ -0,0 +1,25 @@
+{
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Hummel009's Run",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${workspaceFolder}/bin/main",
+            "args": [],
+            "stopAtEntry": false,
+            "cwd": "${workspaceFolder}",
+            "environment": [],
+            "externalConsole": false,
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ],
+            "preLaunchTask": "build"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/appC/.vscode/settings.json b/appC/.vscode/settings.json
new file mode 100644
index 0000000..3191855
--- /dev/null
+++ b/appC/.vscode/settings.json
@@ -0,0 +1,52 @@
+{
+    "files.associations": {
+        "*.rh": "cpp",
+        "array": "cpp",
+        "atomic": "cpp",
+        "bit": "cpp",
+        "*.tcc": "cpp",
+        "cctype": "cpp",
+        "clocale": "cpp",
+        "cmath": "cpp",
+        "compare": "cpp",
+        "concepts": "cpp",
+        "cstdarg": "cpp",
+        "cstddef": "cpp",
+        "cstdint": "cpp",
+        "cstdio": "cpp",
+        "cstdlib": "cpp",
+        "cwchar": "cpp",
+        "cwctype": "cpp",
+        "deque": "cpp",
+        "unordered_map": "cpp",
+        "vector": "cpp",
+        "exception": "cpp",
+        "algorithm": "cpp",
+        "functional": "cpp",
+        "iterator": "cpp",
+        "memory": "cpp",
+        "memory_resource": "cpp",
+        "numeric": "cpp",
+        "optional": "cpp",
+        "random": "cpp",
+        "string": "cpp",
+        "string_view": "cpp",
+        "system_error": "cpp",
+        "tuple": "cpp",
+        "type_traits": "cpp",
+        "utility": "cpp",
+        "initializer_list": "cpp",
+        "iosfwd": "cpp",
+        "iostream": "cpp",
+        "istream": "cpp",
+        "limits": "cpp",
+        "new": "cpp",
+        "ostream": "cpp",
+        "ranges": "cpp",
+        "stdexcept": "cpp",
+        "streambuf": "cpp",
+        "typeinfo": "cpp",
+        "set": "cpp",
+        "math.h": "c"
+    }
+}
\ No newline at end of file
diff --git a/appC/.vscode/tasks.json b/appC/.vscode/tasks.json
new file mode 100644
index 0000000..7164005
--- /dev/null
+++ b/appC/.vscode/tasks.json
@@ -0,0 +1,14 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "build",
+            "type": "shell",
+            "command": "make",
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            }
+        }
+    ]
+}
\ No newline at end of file
diff --git a/appC/Makefile b/appC/Makefile
new file mode 100644
index 0000000..651bb89
--- /dev/null
+++ b/appC/Makefile
@@ -0,0 +1,31 @@
+CXX       := gcc
+CXX_FLAGS := -std=c11 -ggdb
+
+LD_FLAGS  := -luser32 -lgdi32
+
+BIN        := bin
+SRC        := src
+BUILD      := build
+INCLUDE    := -Iinclude
+
+LIBRARIES   :=
+EXECUTABLE  := main
+
+SRCS := $(wildcard $(SRC)/*.cpp)
+OBJS := $(SRCS:$(SRC)/%.cpp=$(BUILD)/%.o)
+
+all: $(BIN)/$(EXECUTABLE)
+
+run: clean all
+	clear
+	./$(BIN)/$(EXECUTABLE)
+
+$(BIN)/$(EXECUTABLE): $(OBJS)
+	$(CXX) $(CXX_FLAGS) $(INCLUDE) $^ -o $@ $(LIBRARIES) $(LD_FLAGS)
+
+$(BUILD)/%.o: $(SRC)/%.cpp
+	$(CXX) $(CXX_FLAGS) $(INCLUDE) -c $< -o $@ $(LIBRARIES) $(LD_FLAGS)
+
+clean:
+	-rm -rf $(BUILD)/*
+	-rm $(BIN)/$(EXECUTABLE)
diff --git a/appC/bin/placeholder.txt b/appC/bin/placeholder.txt
new file mode 100644
index 0000000..e69de29
diff --git a/appC/build/placeholder.txt b/appC/build/placeholder.txt
new file mode 100644
index 0000000..e69de29
diff --git a/appC/include/placeholder.txt b/appC/include/placeholder.txt
new file mode 100644
index 0000000..e69de29
diff --git a/appC/src/Main.cpp b/appC/src/Main.cpp
new file mode 100644
index 0000000..5f5c950
--- /dev/null
+++ b/appC/src/Main.cpp
@@ -0,0 +1,511 @@
+#include <windows.h>
+
+#include <math.h>
+
+#include <stdio.h>
+
+#include <stdlib.h>
+
+#include <string.h>
+
+#define BUTTON_0_ID 0
+#define BUTTON_1_ID 1
+#define BUTTON_2_ID 2
+#define BUTTON_3_ID 3
+#define BUTTON_4_ID 4
+#define BUTTON_5_ID 5
+#define BUTTON_6_ID 6
+#define BUTTON_7_ID 7
+#define BUTTON_8_ID 8
+#define BUTTON_9_ID 9
+#define BUTTON_C_ID 10
+#define BUTTON_DIVIDE_ID 11
+#define BUTTON_DOT_ID 12
+#define BUTTON_EQUALS_ID 13
+#define BUTTON_E_ID 14
+#define BUTTON_FACTORIAL_ID 15
+#define BUTTON_INVERSE_ID 16
+#define BUTTON_MINUS_ID 17
+#define BUTTON_MULTIPLE_ID 18
+#define BUTTON_PI_ID 19
+#define BUTTON_PLUS_ID 20
+#define BUTTON_SQUARE_ID 21
+#define BUTTON_SQUARE_ROOT_ID 22
+#define BUTTON_UNARY_MINUS_ID 23
+
+static HWND field;
+static char *stack_data[3];
+static boolean stack_presence[3];
+
+static int factorial[] = {
+	1,
+	1,
+	2,
+	6,
+	24,
+	120,
+	720,
+	5040,
+	40320,
+	362880,
+	3628800,
+	39916800,
+	479001600};
+
+static void registerButton(HWND window, int id, char *text, int gridX, int gridY);
+static HWND registerField(HWND window);
+static void pushSymbolWrapper(char *symbol);
+static void pushOperation(char *operation);
+static void calculateWrapper();
+
+static LRESULT wndProc(HWND window, UINT msg, WPARAM wParam, LPARAM lParam)
+{
+	int buttonId = LOWORD(wParam);
+	MINMAXINFO *info = (MINMAXINFO *)lParam;
+
+	switch (msg)
+	{
+	case WM_CREATE:
+		field = registerField(window);
+
+		registerButton(window, BUTTON_PI_ID, "p", 0, 0);
+		registerButton(window, BUTTON_E_ID, "e", 1, 0);
+		registerButton(window, BUTTON_C_ID, "C", 2, 0);
+		registerButton(window, BUTTON_FACTORIAL_ID, "x!", 3, 0);
+		registerButton(window, BUTTON_INVERSE_ID, "1/x", 0, 1);
+		registerButton(window, BUTTON_SQUARE_ID, "x^2", 1, 1);
+		registerButton(window, BUTTON_SQUARE_ROOT_ID, "sqrt(x)", 2, 1);
+		registerButton(window, BUTTON_DIVIDE_ID, "/", 3, 1);
+		registerButton(window, BUTTON_7_ID, "7", 0, 2);
+		registerButton(window, BUTTON_8_ID, "8", 1, 2);
+		registerButton(window, BUTTON_9_ID, "9", 2, 2);
+		registerButton(window, BUTTON_MULTIPLE_ID, "*", 3, 2);
+		registerButton(window, BUTTON_4_ID, "4", 0, 3);
+		registerButton(window, BUTTON_5_ID, "5", 1, 3);
+		registerButton(window, BUTTON_6_ID, "6", 2, 3);
+		registerButton(window, BUTTON_MINUS_ID, "-", 3, 3);
+		registerButton(window, BUTTON_1_ID, "1", 0, 4);
+		registerButton(window, BUTTON_2_ID, "2", 1, 4);
+		registerButton(window, BUTTON_3_ID, "3", 2, 4);
+		registerButton(window, BUTTON_PLUS_ID, "+", 3, 4);
+		registerButton(window, BUTTON_UNARY_MINUS_ID, "-", 0, 5);
+		registerButton(window, BUTTON_0_ID, "0", 1, 5);
+		registerButton(window, BUTTON_DOT_ID, ".", 2, 5);
+		registerButton(window, BUTTON_EQUALS_ID, "=", 3, 5);
+		break;
+	case WM_COMMAND:
+		switch (buttonId)
+		{
+		case BUTTON_0_ID:
+			pushSymbolWrapper("0");
+			break;
+		case BUTTON_1_ID:
+			pushSymbolWrapper("1");
+			break;
+		case BUTTON_2_ID:
+			pushSymbolWrapper("2");
+			break;
+		case BUTTON_3_ID:
+			pushSymbolWrapper("3");
+			break;
+		case BUTTON_4_ID:
+			pushSymbolWrapper("4");
+			break;
+		case BUTTON_5_ID:
+			pushSymbolWrapper("5");
+			break;
+		case BUTTON_6_ID:
+			pushSymbolWrapper("6");
+			break;
+		case BUTTON_7_ID:
+			pushSymbolWrapper("7");
+			break;
+		case BUTTON_8_ID:
+			pushSymbolWrapper("8");
+			break;
+		case BUTTON_9_ID:
+			pushSymbolWrapper("9");
+			break;
+		case BUTTON_E_ID:
+			pushSymbolWrapper("2.72");
+			break;
+		case BUTTON_PI_ID:
+			pushSymbolWrapper("3.14");
+			break;
+		case BUTTON_DOT_ID:
+			pushSymbolWrapper(".");
+			break;
+		case BUTTON_UNARY_MINUS_ID:
+			pushSymbolWrapper("-");
+			break;
+		case BUTTON_C_ID:
+			stack_data[0] = "";
+			stack_data[1] = "";
+			stack_data[2] = "";
+			stack_presence[0] = FALSE;
+			stack_presence[1] = FALSE;
+			stack_presence[2] = FALSE;
+			SetWindowText(field, "");
+			break;
+		case BUTTON_DIVIDE_ID:
+			pushOperation("/");
+			break;
+		case BUTTON_MULTIPLE_ID:
+			pushOperation("*");
+			break;
+		case BUTTON_MINUS_ID:
+			pushOperation("-");
+			break;
+		case BUTTON_PLUS_ID:
+			pushOperation("+");
+			break;
+		case BUTTON_FACTORIAL_ID:
+			pushOperation("!");
+			break;
+		case BUTTON_SQUARE_ID:
+			pushOperation("s");
+			break;
+		case BUTTON_INVERSE_ID:
+			pushOperation("i");
+			break;
+		case BUTTON_SQUARE_ROOT_ID:
+			pushOperation("r");
+			break;
+		case BUTTON_EQUALS_ID:
+			calculateWrapper();
+			break;
+		}
+		break;
+
+	case WM_GETMINMAXINFO:
+		info->ptMinTrackSize.x = 260;
+		info->ptMinTrackSize.y = 453;
+		info->ptMaxTrackSize.x = 260;
+		info->ptMaxTrackSize.y = 453;
+		break;
+
+	case WM_CLOSE:
+		DestroyWindow(window);
+		break;
+	case WM_DESTROY:
+		PostQuitMessage(0);
+		break;
+	}
+	return DefWindowProcA(window, msg, wParam, lParam);
+}
+
+int max(int a, int b)
+{
+	return (a > b) ? a : b;
+}
+
+int main()
+{
+	char *className = "HummelCalculator";
+
+	WNDCLASSEX wc;
+	wc.cbSize = sizeof(WNDCLASSEX);
+	wc.style = CS_HREDRAW | CS_VREDRAW;
+	wc.lpfnWndProc = wndProc;
+	wc.cbClsExtra = 0;
+	wc.cbWndExtra = 0;
+	wc.hInstance = NULL;
+	wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
+	wc.hCursor = LoadCursor(NULL, IDC_ARROW);
+	wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
+	wc.lpszMenuName = NULL;
+	wc.lpszClassName = className;
+	wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
+
+	RegisterClassExA(&wc);
+
+	int screenWidth = GetSystemMetrics(SM_CXSCREEN);
+	int screenHeight = GetSystemMetrics(SM_CYSCREEN);
+
+	int windowWidth = 260;
+	int windowHeight = 453;
+
+	int windowX = max(0, (screenWidth - windowWidth) / 2);
+	int windowY = max(0, (screenHeight - windowHeight) / 2);
+
+	char *windowTitle = "WinAPI";
+	HWND window = CreateWindowExA(
+		WS_EX_CLIENTEDGE,
+		className,
+		windowTitle,
+		WS_OVERLAPPEDWINDOW,
+		windowX,
+		windowY,
+		windowWidth,
+		windowHeight,
+		NULL,
+		NULL,
+		NULL,
+		NULL);
+
+	ShowWindow(window, SW_SHOW);
+	UpdateWindow(window);
+
+	MSG msg;
+	while (GetMessageA(&msg, NULL, 0u, 0u) != 0)
+	{
+		TranslateMessage(&msg);
+		DispatchMessageA(&msg);
+	}
+}
+
+static void push(char *str)
+{
+	if (stack_presence[0] == FALSE)
+	{
+		stack_data[0] = str;
+		stack_presence[0] = TRUE;
+	}
+	if (stack_presence[1] == FALSE)
+	{
+		stack_data[1] = str;
+		stack_presence[1] = TRUE;
+	}
+	if (stack_presence[2] == FALSE)
+	{
+		stack_data[2] = str;
+		stack_presence[2] = TRUE;
+	}
+}
+
+static void calculateWrapper()
+{
+	int length = GetWindowTextLength(field);
+	if (length > 0)
+	{
+		char *buffer = (char *)malloc((length + 1) * sizeof(char));
+		GetWindowText(field, buffer, length + 1);
+		if (stack_presence[0] == TRUE && stack_presence[1] == TRUE)
+		{
+			char *op = stack_data[1];
+
+			if (strcmp(op, "+") == 0 || strcmp(op, "-") == 0 || strcmp(op, "*") == 0 || strcmp(op, "/") == 0)
+			{
+				push(buffer);
+				free(buffer);
+
+				double operand1 = strtod(stack_data[0], NULL);
+				double operand2 = strtod(stack_data[2], NULL);
+
+				double result;
+				if (strcmp(op, "+") == 0)
+				{
+					result = operand1 + operand2;
+				}
+				else if (strcmp(op, "-") == 0)
+				{
+					result = operand1 - operand2;
+				}
+				else if (strcmp(op, "*") == 0)
+				{
+					result = operand1 * operand2;
+				}
+				else if (strcmp(op, "/") == 0)
+				{
+					result = operand1 / operand2;
+				}
+				else
+				{
+					goto exception;
+				}
+
+				stack_data[0] = "";
+				stack_data[1] = "";
+				stack_data[2] = "";
+				stack_presence[0] = FALSE;
+				stack_presence[1] = FALSE;
+				stack_presence[2] = FALSE;
+				char *str;
+				sprintf(str, "%f", result);
+
+				SetWindowText(field, str);
+			}
+			else if (strcmp(op, "!") == 0 || strcmp(op, "s") == 0 || strcmp(op, "i") == 0 || strcmp(op, "r") == 0)
+			{
+				double operand = strtod(stack_data[0], NULL);
+
+				double result;
+				if (strcmp(op, "!") == 0)
+				{
+					result = factorial[(int)operand];
+				}
+				else if (strcmp(op, "s") == 0)
+				{
+					result = operand * operand;
+				}
+				else if (strcmp(op, "i") == 0)
+				{
+					result = 1.0 / operand;
+				}
+				else if (strcmp(op, "r") == 0)
+				{
+					result = sqrt(operand);
+				}
+				else
+				{
+					goto exception;
+				}
+
+				stack_data[0] = "";
+				stack_data[1] = "";
+				stack_data[2] = "";
+				stack_presence[0] = FALSE;
+				stack_presence[1] = FALSE;
+				stack_presence[2] = FALSE;
+
+				char *str;
+				sprintf(str, "%f", result);
+				SetWindowText(field, str);
+			}
+		}
+		return;
+
+	exception:
+		stack_data[0] = "";
+		stack_data[1] = "";
+		stack_data[2] = "";
+		stack_presence[0] = FALSE;
+		stack_presence[1] = FALSE;
+		stack_presence[2] = FALSE;
+		SetWindowText(field, "Error!");
+	}
+}
+
+static void pushOperation(char *operation)
+{
+	int length = GetWindowTextLength(field);
+	if (length > 0)
+	{
+		char *buffer = (char *)malloc((length + 1) * sizeof(char));
+		GetWindowText(field, buffer, length + 1);
+		if (stack_presence[0] == FALSE)
+		{
+			push(buffer);
+			free(buffer);
+			push(operation);
+			SetWindowText(field, "");
+		}
+		else
+		{
+			stack_data[0] = "";
+			stack_data[1] = "";
+			stack_data[2] = "";
+			stack_presence[0] = FALSE;
+			stack_presence[1] = FALSE;
+			stack_presence[2] = FALSE;
+			SetWindowText(field, "Error!");
+		}
+	}
+}
+
+static void pushSymbol(char *number);
+static void pushSymbolWrapper(char *symbol)
+{
+	int length = GetWindowTextLength(field);
+	if (length > 0)
+	{
+		char *buffer = (char *)malloc((length + 1) * sizeof(char));
+		GetWindowText(field, buffer, length + 1);
+		if (strcmp(symbol, "3.14") == 0 || strcmp(symbol, "2.72") == 0)
+		{
+			if (strchr(buffer, '.') == NULL)
+			{
+				pushSymbol(symbol);
+			}
+		}
+		else if (strcmp(symbol, ".") == 0)
+		{
+			if (strchr(buffer, '.') == NULL && strlen(buffer) != 0)
+			{
+				pushSymbol(symbol);
+			}
+		}
+		else if (strcmp(symbol, "-") == 0)
+		{
+			if (strlen(buffer) == 0)
+			{
+				pushSymbol(symbol);
+			}
+		}
+		else
+		{
+			if (strlen(buffer) == 0)
+			{
+				pushSymbol(symbol);
+			}
+			else
+			{
+				char *op = stack_data[1];
+
+				if (strcmp(op, "!") != 0 && strcmp(op, "s") != 0 && strcmp(op, "i") != 0 && strcmp(op, "r") != 0)
+				{
+					pushSymbol(symbol);
+				}
+			}
+		}
+		free(buffer);
+	}
+}
+
+static void pushSymbol(char *number)
+{
+	int length = GetWindowTextLength(field);
+	if (length > 0)
+	{
+		char *buffer = (char *)malloc((length + 1) * sizeof(char));
+
+		GetWindowText(field, buffer, length + 1);
+		if (strcmp(buffer, "Error!") == 0)
+		{
+			SetWindowText(field, number);
+		}
+		else
+		{
+			strcat(buffer, number);
+			SetWindowText(field, buffer);
+		}
+		free(buffer);
+	}
+}
+
+static HWND registerField(HWND window)
+{
+	return CreateWindowEx(
+		0,
+		"STATIC",
+		"",
+		WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,
+		0,
+		0,
+		238,
+		50,
+		window,
+		NULL,
+		NULL,
+		NULL);
+}
+
+static void registerButton(HWND window, int id, char *text, int gridX, int gridY)
+{
+	int buttonWidth = 60;
+	int buttonHeight = 60;
+
+	CreateWindowEx(
+		0,
+		"BUTTON",
+		text,
+		WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,
+		buttonWidth * gridX,
+		50 + buttonHeight * gridY,
+		buttonWidth,
+		buttonHeight,
+		window,
+		(HMENU)id,
+		NULL,
+		NULL);
+}
\ No newline at end of file