🐍 Python Pattern Challenge — Day 19

Pattern printing is a simple way to improve your Python loops, spacing, repetition, and logical thinking. For Day 19, let's create a simple Right-Side Arrow Star Pattern ⭐.

This pattern is easy to understand but still gives you good practice with increasing and decreasing star counts.

🎯 Today's Challenge

Write a Python program to print:

Best and cleanest code will be rewarded! 🏆

---

Solution 1 — Using for Loop

n = 6

for i in range(1, n + 1):
    print("* " * i)

for i in range(n - 1, 0, -1):
    print("* " * i)

How it works

The first loop increases the number of stars:

*
* *
* * *
* * * *
* * * * *
* * * * * *

The second loop decreases them:

* * * * *
* * * *
* * *
* *
*

Together, they create the complete arrow pattern.

---

Solution 2 — Using a Single Loop

n = 6

for i in list(range(1, n + 1)) + list(range(n - 1, 0, -1)):
    print("* " * i)
The sequence:

[1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1]

controls how many stars are printed on each row.

---

Solution 3 — Using a Function

def star_arrow(n):

    for i in list(range(1, n + 1)) + list(range(n - 1, 0, -1)):
        print("* " * i)


star_arrow(6)

Now you can easily change the size:

star_arrow(10)

and create a larger pattern.

---

⚡ Short & Clean Code

for i in [1,2,3,4,5,6,5,4,3,2,1]:
    print("* " * i)

🔥 Just one loop creates the complete pattern.

---

🚀 Challenge Yourself

Can you modify this pattern:

• Take the size using input()?
• Create it using a while loop?
• Reverse the arrow?
• Replace * with # or another symbol?
• Create a hollow version?
• Move the pattern toward the left or right?

Drop your solution below! 👇

19 Days. 19 Patterns. Stronger Python Logic. 🐍🔥

Learn • Practice • Grow with CLCODING 🚀

Read More

🌌 Python Turtle The Neon Wave Tunnel

 

Code:

import turtle import math import time screen = turtle.Screen() screen.setup(700, 700) screen.bgcolor("#020208") t = turtle.Turtle() t.hideturtle() t.speed(0) t.width(2) colors = [ "#00ffff", "#7c4dff", "#ff2d75", "#00ff9d", "#ffe600" ] for layer in range(35): t.color(colors[layer % len(colors)]) t.penup() for i in range(180): x = -260 + i * 3 wave = math.sin(i * 0.09 + layer * 0.35) * (35 + layer) y = wave + layer * 2 if i == 0: t.goto(x, y) t.pendown() else: t.goto(x, y) screen.update() time.sleep(0.003) time.sleep(0.08) # ✨ Center glow for r in range(30, 2, -3): t.penup() t.goto(0, -r) t.dot(r, colors[r % len(colors)]) screen.update() time.sleep(0.06) turtle.done()

Explanation:

1. Import Libraries

import turtle

import math

import time

turtle → Creates the drawing.

math → Calculates the wave pattern.

time → Controls animation speed.

2. Create the Screen

screen = turtle.Screen()

screen.setup(700, 700)

screen.bgcolor("#020208")

Creates a 700 × 700 canvas.

Sets a dark background.

3. Configure the Turtle

t = turtle.Turtle()

t.hideturtle()

t.speed(0)

t.width(2)

Creates the turtle.

Hides the turtle cursor.

Sets maximum speed.

Sets line thickness to 2.

4. Define Neon Colors

colors = [

    "#00ffff", "#7c4dff",

    "#ff2d75", "#00ff9d",

    "#ffe600"

]

Stores five neon colors.

These colors are used for different wave layers.

5. Create Multiple Wave Layers

for layer in range(35):

Creates 35 separate wave layers.

Each layer forms part of the tunnel effect.

6. Select the Layer Color

t.color(colors[layer % len(colors)])

Cycles through the neon colors.

layer % len(colors) prevents the index from going out of range.

7. Prepare for Drawing

t.penup()

Lifts the pen before moving to the starting point.

8. Generate Wave Points

for i in range(180):

Creates 180 points for every wave.

9. Calculate X Position

x = -260 + i * 3

Starts at -260.

Moves 3 pixels to the right each time.

10. Calculate the Wave

wave = math.sin(i * 0.09 + layer * 0.35) * (35 + layer)

Uses sin() to create a smooth wave.

layer * 0.35 shifts each layer.

(35 + layer) gradually increases the wave size.

11. Calculate Y Position

y = wave + layer * 2

Combines the wave movement with the layer offset.

Moves each layer slightly upward.

12. Start the Wave

if i == 0:

    t.goto(x, y)

    t.pendown()

Moves to the first point without drawing.

Then starts drawing the wave.

13. Continue the Wave

else:

    t.goto(x, y)

Connects each calculated point.

Creates the continuous wave line.

14. Animate the Wave

screen.update()

time.sleep(0.003)

Updates the screen.

Adds a tiny delay for smooth animation.

15. Pause Between Layers

time.sleep(0.08)

Adds a short pause after each wave layer.

Makes the tunnel formation visible.

16. Create the Center Glow

for r in range(30, 2, -3):

Creates several shrinking circles.

The radius decreases from 30 to 3.

17. Draw the Glow

t.penup()

t.goto(0, -r)

t.dot(r, colors[r % len(colors)])

Moves to the center.

Draws colorful dots of decreasing size.

Creates a glowing-center effect.

18. Animate the Glow

screen.update()

time.sleep(0.06)

Updates the screen.

Adds a small delay between glow layers.

19. Finish

turtle.done()

Keeps the Turtle window open.

Ends the animation.

Read More

Python Coding Challenge - Question with Answer (ID 031026)

 

Explanation:

🟢 Line 1: Complete Code

print(10 // 3 * 2 + 10 % 3 ** 1)

We need to evaluate the operators according to Python's operator precedence.

🟡 Step 1: Evaluate Exponentiation **

Exponentiation has higher precedence than //, *, %, and +.

3 ** 1

So:

3 ** 1 = 3

Expression becomes:

10 // 3 * 2 + 10 % 3

🔵 Step 2: Evaluate //

Now:

10 // 3

Floor division gives:

10 // 3 = 3

Expression becomes:

3 * 2 + 10 % 3

🟣 Step 3: Evaluate *

3 * 2 = 6

Expression becomes:

6 + 10 % 3

🟠 Step 4: Evaluate %

Modulo gives the remainder:

10 % 3

Since:

10 = 3 × 3 + 1

Therefore:

10 % 3 = 1

Expression becomes:

6 + 1

🟢 Step 5: Addition

6 + 1 = 7

So Python effectively executes:

print(7)

🎯 Final Output

7

Books: PYTHON LOOPS MASTERY

Read More

Python Coding challenge - Day 1273| What is the output of the following Python Code?

 

Code Explanation:

1. 🏗️ Creating the Dictionary Subclass

class D(dict):

Here, D is a custom class that inherits from dict.

Therefore, objects of D behave like dictionaries, but we can also add custom behavior.

2. 🔍 Defining __missing__()

def __missing__(self, key):

__missing__() is a special dictionary method.

Python calls it when:

d[key]

is used and the key does not exist.

It is important that __missing__() is triggered by dictionary indexing, not by every dictionary lookup method.

3. 📏 Returning the Key Length

return len(key)

The missing key will be "python".

Therefore:

len("python") = 6

So __missing__() returns:

6

4. 🗂️ Creating the Dictionary

d = D()

An empty object of class D is created.

Initially:

d = {}

There is no "python" key.

5. 🎯 Accessing the Missing Key

x = d["python"]

Python looks for "python" inside d.

It doesn't find it.

Because D defines __missing__(), Python calls:

__missing__("python")

Then:

len("python")

returns:

6

Therefore:

x = 6

6. ⚠️ The Important .get() Difference

y = d.get("python")

This is the tricky line.

Even though "python" is missing, .get() does not call __missing__().

Since there is no "python" key, .get() returns:

None

Therefore:

y = None

7. 🖨️ Print the Result

print(x, y)

We have:

x = 6

y = None

So the output is:

6 None

Book: 400 Days Python Coding Challenges with Explanation

Read More

Python Coding challenge - Day 1272| What is the output of the following Python Code?

 

Code Explanation:

1. 🔧 Define the Generator Function

def gen():

This creates a function named gen.

Because the function contains yield, it becomes a generator function.

A generator does not execute its entire body immediately.

2. 📌 Initialize x

x = 1

When the generator starts running, x is initialized to:

x = 1

3. 🔁 Check the while Condition

while x < 10:

Python checks whether:

1 < 10

This is True, so the loop starts.

4. 🎁 First yield

yield x

At this moment:

yield 1

The generator pauses and sends 1 to whoever called next(g).

So:

next(g)

returns:

1

Important: yield pauses the function instead of ending it.

5. 🔄 Resume and Multiply

x *= 3

When the next next(g) is called, execution resumes from where it paused.

Now:

x = 1 × 3

x = 3

6. 🔁 Second Loop Check

Python reaches:

while x < 10:

Now:

3 < 10

is True.

So the loop continues.

7. 🎁 Second yield

yield x

Now the generator yields:

3

Therefore the second:

next(g)

returns 3.

8. 🖨️ print() Executes

print(next(g), next(g))

Python evaluates the arguments from left to right:

First next(g)  → 1

Second next(g) → 3

So the final output is:

1 3

🔄 Generator Flow

gen()

 ↓

x = 1

 ↓

yield 1

 ↓

pause

 ↓

next(g)

 ↓

x = 3

 ↓

yield 3

 ↓

pause

💡 Key Interview Trick

next() does not restart the generator.

It resumes execution from the previous yield point.

So the sequence produced by this generator would be:

1 → 3 → 9

The two next() calls consume only:

1 → 3

Hence:

✅ Final Answer

1 3

Book: 500 Days Python Coding Challenges with Explanation

Read More