Day-12 Added

Author: Dark-Vinaal

Day-11/notes.md

@@ -121,4 +121,4 @@ Here, marks >= 70 is True, so it prints “Grade: B”.
 
 📘 *Next step (Day 12):*  
 
-I’ll explore **Control Structure - Iterative Statements**.
+I’ll explore **Control Structure - Iterative Statements (while loop)**.

Day-12/notes.md

@@ -0,0 +1,139 @@
+# 🗓️ Day 12 — Iterative Statements (While Loop)
+
+## 🎯 Topics Covered
+- What are Iterative Statements?
+- Understanding the `while` Loop
+- Key Steps: 
+  - 1. Initialization, 
+  - 2. Condition, 
+  - 3. Updating.
+
+---
+
+## 🔁 What are Iterative Statements?
+
+Iterative statements are used to **repeat a block of code multiple times** based on a condition.  
+In Python, we mainly use two types of loops:
+- `while` loop
+- `for` loop (will be covered later)
+
+---
+
+## 🌀 The `while` Loop
+
+The **`while` loop** executes a block of code **as long as the given condition is True**.
+
+### 🧠 Syntax:
+```python
+while condition:
+    # block of code
+```
+
+---
+
+### ⚙️ Components of a While Loop
+
+A while loop generally has three main parts:
+
+| Step                  | Description                                            | Example                 |
+| --------------------- | ------------------------------------------------------ | ----------------------- |
+| **1. Initialization** | Assign starting value to variable                      | `i = 1`                 |
+| **2. Condition**      | Loop continues until condition becomes False           | `while i <= 5:`         |
+| **3. Updating**       | Change variable value to move toward stopping the loop | `i = i + 1` or `i += 1` |
+
+---
+
+### 💻 Example — Print Numbers from 1 to 5
+```python
+# Initialization
+i = 1
+
+# Condition
+while i <= 5:
+    print(i)
+    
+    # Updating
+    i += 1
+```
+
+### 🧠 Output:
+```python
+1
+2
+3
+4
+5
+```
+
+---
+
+### ✅ Explanation:
+
+- i starts at 1.
+- The condition i <= 5 is checked each time.
+- After printing, i is increased by 1.
+- When i becomes 6, the condition fails, and the loop stops.
+
+---
+
+## ⚠️ Infinite Loop Example
+
+If you forget to update the loop variable, it will run forever.
+
+### 💻 Example:
+```python
+x = 1
+
+while x <= 5:
+    print("Infinite Loop!")
+    # Missing update (x += 1)
+```
+
+### 🧾 Output:
+
+This loop runs endlessly, because x never changes, and the condition x <= 5 is always True.
+
+---
+
+## 🧩 Using Break in While Loop
+
+You can stop a loop anytime using the break statement.
+
+### 💻 Example:
+```python
+i = 1
+
+while i <= 10:
+    if i == 6:
+        break
+    print(i)
+    i += 1
+```
+
+### 🧠 Output:
+```python
+1
+2
+3
+4
+5
+```
+✅ The loop stops when i becomes 6.
+
+---
+
+## 🧠 Summary
+
+| Concept        | Description                     | Example         |
+| -------------- | ------------------------------- | --------------- |
+| Initialization | Variable setup before loop      | `i = 1`         |
+| Condition      | Checked before each iteration   | `while i <= 5:` |
+| Updating       | Increment/decrement inside loop | `i += 1`        |
+| Infinite Loop  | Loop without update             | `while True:`   |
+| Break          | Stops loop immediately          | `break`         |
+
+---
+
+📘 *Next step (Day 13):*  
+
+I’ll explore **Control Structure - Iterative Statements (for loop)**.