My Contribution to this Repository

solutions/Rishav Mitra/Code/ToDo App/.gitignore

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+__pycache__
+
+*.db

solutions/Rishav Mitra/Code/ToDo App/backend.py

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+# This file contains all the functions that will be used in the app
+import sqlite3
+
+def createTable():
+	conn = sqlite3.connect('tasksDatabase.db')
+	c = conn.cursor()
+
+	c.execute("""CREATE TABLE tasks(
+				id integer primary key autoincrement,
+				name text,
+				status text)""")
+
+	conn.commit()
+	conn.close()
+
+def addNewTask(task):
+	conn = sqlite3.connect('tasksDatabase.db')
+	c = conn.cursor()
+
+	c.execute("INSERT INTO tasks (name, status) VALUES (?, ?)", (task, 'pending'))
+
+	conn.commit()
+	conn.close()
+
+def markTaskAsDone(idc):
+	conn = sqlite3.connect('tasksDatabase.db')
+	c = conn.cursor()
+
+	c.execute("UPDATE tasks SET status = 'done' WHERE id = (?)", (idc, ))
+
+	conn.commit()
+	conn.close()
+
+def removeDoneTask():
+	conn = sqlite3.connect('tasksDatabase.db')
+	c = conn.cursor()
+
+	c.execute("DELETE from tasks WHERE status = 'done'")
+
+	conn.commit()
+	conn.close()
+
+def showAllTasks():
+	conn = sqlite3.connect('tasksDatabase.db')
+	c = conn.cursor()
+
+	c.execute("SELECT * FROM tasks")
+
+	rows = c.fetchall()
+	return rows

solutions/Rishav Mitra/Code/ToDo App/taskManagerSqlite.py

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+import backend # This is the local file called 'backend.py'
+import os
+from tkinter import *
+
+root = Tk()
+root.geometry("620x450")
+root.title("To Do App")
+
+if not os.path.exists('tasksDatabase.db'):
+	backend.createTable()
+
+# Implement the basic functionalities
+def add():
+	task = newTaskEntry.get()
+	backend.addNewTask(task)
+	show()
+
+def done():
+	try:
+		idc = doneEntry.get()
+		backend.markTaskAsDone(idc)
+	except Exception as e:
+		doneEntry.insert("end", "Something was wrong")
+	finally:
+		show()
+
+def remove():
+	backend.removeDoneTask()
+	show()
+
+def show():
+	tasks.delete(1.0, END)
+	rows = backend.showAllTasks()
+	if len(rows) == 0:
+		tasks.insert("end", "No tasks added")
+	else:
+		for row in rows:
+			tasks.insert("end", f"{row[0]} | {row[1]} | {row[2]} \n\n")
+
+# Create the layout
+newTaskLabel = Label(root, text = "Add a new task")
+newTaskLabel.grid(row = 0, column = 0, padx = 40)
+
+newTaskEntry = Entry(root, font = "Arial")
+newTaskEntry.grid(row = 1, column = 0, padx = 25, ipady = 5)
+
+addTaskBtn = Button(root, text = "Add", command = add)
+addTaskBtn.grid(row = 1, column = 1, ipadx = 5)
+
+tasks = Text(root, height = 20, width = 40, font = "Arial")
+tasks.grid(row = 2, column = 0, rowspan = 4, padx = 10, pady = 10)
+
+doneLabel = Label(root, text = "Enter the id of any task you've completed")
+doneLabel.grid(row = 2, column = 1)
+
+doneEntry = Entry(root, font = "Arial")
+doneEntry.grid(row = 3, column = 1)
+
+okBtn = Button(root, text = "OK", command = done)
+okBtn.grid(row = 4, column = 1)
+
+removeBtn = Button(root, text = "Remove Done Tasks", command = remove)
+removeBtn.grid(row = 5, column = 1)
+
+show()
+root.mainloop()

solutions/Rishav Mitra/Code/bmi_calculator.py

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+from tkinter import *
+
+# Define the available units
+massUnitOptions = ["kg", "lb"]
+heightUnitOptions = ["m", "cm", "inches"]
+
+root = Tk()
+root.title("BMI Calculator")
+root.geometry("500x300")
+
+# submit() function performs the necessary calculations
+def submit():
+	mass = float(massInput.get())
+	height = float(heightInput.get())
+	mass_unit = massUnits.get()
+	height_unit = heightUnits.get()
+
+	if mass_unit == "lb":
+		mass /= 2.205
+	if height_unit == "cm":
+		height /= 100
+	if height_unit == "inches":
+		height /= 39.37
+
+	bmi = mass/(height**2)
+	bmiLabel.config(text = round(bmi, 3))
+
+massUnits = StringVar()
+massUnits.set(massUnitOptions[0])
+
+heightUnits = StringVar()
+heightUnits.set(heightUnitOptions[0])
+
+# arrange all the widgets on the screen
+massLabel = Label(root, text = "Enter your weight :", font = "bold")
+massLabel.grid(row = 0, column = 0, padx = 35, pady = 20)
+
+massInput = Entry(root, justify = "center", font = "bold")
+massInput.grid(row = 0, column = 1)
+
+massOptions = OptionMenu(root, massUnits, *massUnitOptions)
+massOptions.grid(row = 0, column = 2, padx = 5)
+
+heightLabel = Label(root, text = "Enter your height :", font = "bold")
+heightLabel.grid(row = 1, column = 0)
+
+heightInput = Entry(root, justify = "center", font = "bold")
+heightInput.grid(row = 1, column = 1)
+
+heightOptions = OptionMenu(root, heightUnits, *heightUnitOptions)
+heightOptions.grid(row = 1, column = 2, padx = 5)
+
+submitBtn = Button(root, text = "OK", command = submit, padx = 10)
+submitBtn.grid(row = 2, column = 0, columnspan = 2, pady = 25)
+
+info = Label(root, text = "Your Body Mass Index (BMI) is", font = "bold")
+info.grid(row = 3, column = 0, columnspan = 2)
+
+bmiLabel = Label(root, text = "", font = "bold")
+bmiLabel.grid(row = 4, column = 0, columnspan = 2)
+
+root.mainloop()

solutions/Rishav Mitra/Code/caesar_cipher.py

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+# This is a command-line application
+import string
+
+# Getting the list of alphabets
+UPPERCASE_LETTERS = string.ascii_uppercase
+LOWERCASE_LETTERS = string.ascii_lowercase
+
+# function to encrypt the message
+def encrypt(message, shift):
+	encrypted_message = ""
+	# Algorithm for encryption
+	for char in message:
+		if char in UPPERCASE_LETTERS:
+			new_char = UPPERCASE_LETTERS[(UPPERCASE_LETTERS.index(char) + shift) % 26]
+		elif char in LOWERCASE_LETTERS:
+			new_char = LOWERCASE_LETTERS[(LOWERCASE_LETTERS.index(char) + shift) % 26]
+		else:
+			new_char = char
+
+		encrypted_message += new_char
+
+	return encrypted_message
+
+# function to decrypt the message
+def decrypt(message, shift):
+	decrypted_message = ""
+	# Algorithm for decryption
+	for char in message:
+		if char in UPPERCASE_LETTERS:
+			new_char = UPPERCASE_LETTERS[(UPPERCASE_LETTERS.index(char) - shift) % 26]
+		elif char in LOWERCASE_LETTERS:
+			new_char = LOWERCASE_LETTERS[(LOWERCASE_LETTERS.index(char) - shift) % 26]
+		else:
+			new_char = char
+
+		decrypted_message += new_char
+
+	return decrypted_message
+
+if __name__ == '__main__':
+	option = input("Do you want to [e]ncrypt or [d]ecrypt your message ? ")
+
+	if option in ['e', 'd']:
+		message = input("Enter your message : ")
+
+		print("Enter the shift of the cipher \nPositive values => Right shift \nNegative values => Left shift")
+		shift = int(input())
+
+		if option == 'e':
+			print(encrypt(message, shift))
+		elif option == 'd':
+			print(decrypt(message, shift))
+
+	else:
+		print("Please enter a valid option !")

solutions/Rishav Mitra/README.md

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+@Rishav-12
+Rishav Mitra
+
+* I have a few of my own projects on GitHub. This is my first contribution to an Open-source GitHub project
+* My GitHub Link : www.github.com/Rishav-12
+
+### About the Code
+* BMI Calculator:
+	* It basically takes in the weight and the height which the user inputs, and displays their Body Mass Index (BMI)
+	* It is a GUI-based application made with Tkinter
+
+* Caesar Cipher:
+	* It has two functions, one to encrypt and the other to decrypt the message
+	* The users decide whether they want to encrypt or decrypt their message, type in the message and the shift value, and the program generates the appropriate encrypted/decrypted message
+	* This is a command line interface application
+
+* ToDo App:
+	* A fully functional to-do list application with a front-end UI and a SQLite3 back-end
+	* Maintains a database that contains a table with all the tasks and their current status
+	* Has all the basic functions of a to-do application like adding tasks, marking tasks as done and removing them from the database