module3

Control Structures in Python

#Task 1: Check if a Number is Even or Odd Problem Statement: Write a Python program that:

1. Takes an integer input from the user.
2. Checks whether the number is even or odd using an if-else statement.
3. Displays the result accordingly.

This Python script checks whether a given number is even or odd. Here's a detailed explanation of how it works:

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🔍 Step-by-step Description:

1. Take Input from the User:

   num = input("Enter a number : ")

   • Prompts the user to enter a number.
   • The input is initially read as a string.

2. Convert Input to Integer:

   num = int(num)

   • Converts the string input to an integer so arithmetic operations can be performed.

3. Check Even or Odd:

   if(num % 2 == 0):
       print(f"num is an even number.")
   else:
       print(f"num is an odd number.")

   • Uses the modulus operator % to check the remainder when num is divided by 2:

     • If num % 2 == 0, the number is even.
     • Otherwise, it is odd.

   • Prints the appropriate message.

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✅ Example Output:

Example 1:

Enter a number : 10
num is an even number.

Example 2:

Enter a number : 7
num is an odd number.

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🧠 Key Concepts Used:

• input() for taking user input
• int() for type conversion
• % modulus operator
• if-else conditional statements
• f-string formatting for clean output

Task 2: Sum of Integers from 1 to 50 Using a Loop

Problem Statement: Write a Python program that:

1. Uses a for loop to iterate over numbers from 1 to 50.
2. Calculates the sum of all integers in this range.
3. Displays the final sum.

This Python script calculates the sum of all integers from 1 to 50 using a for loop. Here's a detailed explanation of how it works:

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🔍 Step-by-step Description:

1. Initialize a Sum Variable:

   sumTotal = 0

   • A variable named sumTotal is initialized to 0.
   • It will be used to keep a running total of the sum.

2. Loop Through Numbers 1 to 50:

   for num in range(1, 51):
       sumTotal = sumTotal + int(num)

   • range(1, 51) generates numbers from 1 to 50 (note: the end is exclusive, so 51 is not included).

   • In each iteration of the loop:

     • The current number num is added to sumTotal.
     • int(num) is used, though it's actually unnecessary since num is already an integer from range().

3. Print the Final Sum:

   print(f"The sum of numbers from 1 to 50 is : {sumTotal}")

   • After the loop completes, the total sum is printed using an f-string.

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✅ Expected Output:

The sum of numbers from 1 to 50 is : 1275

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🧠 Key Concepts Used:

• for loop
• range() function
• Integer addition and accumulation
• f-string for formatted output