Welcome to Day-3 learning Python !!! Hope everyone is staying safe !!! Stay Healthy and Keep Learning.

Tables Of Contents:

1. Control Flow If/Else and conditional operators
2. Nested If statements and elif Statements
3. Multiple If statements in succession
4. Logical Operators

1. Control Flow If/Else and conditional operators

Syntax Code Block:

if condition:
  print("execute this statement if the condition is True")
else:
  print("execute this statement if the condition is not True")

Flow Chart

Example-1:

print("Welcome to the rollercoaster!")
height = int(input("What is your height in cm? "))

# if height > 120:
#   print("you can ride the roller coaster")
# else:
#   print("Sorry you can't ride the roller coaster")

# Note: If the height is exactly 120 it prints the else condition block to print the if conditional block for height 120cm you need to specify is equal to (==) OR (>=) "

if height == 120:
  print("you can ride the roller coaster")
else:
  print("Sorry you can't ride the roller coaster")

Quiz:

Odd or Even

Instructions

Write a program that works out whether if a given number is an odd or even number.

Even numbers can be divided by 2 with no remainder.

e.g. 86 is even because 86 ÷ 2 = 43

43 does not have any decimal places. Therefore the division is clean.

e.g. 59 is odd because 59 ÷ 2 = 29.5

29.5 is not a whole number, it has decimal places. Therefore there is a remainder of 0.5, so the division is not clean.

The modulo is written as a percentage sign (%) in Python. It gives you the remainder after a division.

e.g.

6 ÷ 2 = 3 with no remainder.

6 % 2 = 0

5 ÷ 2 = 2 x 2 + 1, remainder is 1.

5 % 2 = 1

14 ÷ 4 = 3 x 4 + 2, remainder is 2.

14 % 4 = 2

Warning your output should match the Example Output format exactly, even the positions of the commas and full stops.

Example Input 1

43

Example Output 1

This is an odd number.

Example Input 2

94

Example Output 2

This is an even number.

e.g. When you hit run, this is what should happen:

Hint

1. All even numbers can be divided by 2 with 0 remainder.
2. Try some using the modulo with some odd numbers e.g.

3 % 2

5 % 2

7 % 2

Then try using the modulo with some even numbers e.g.

4 % 2

6 % 2

8 % 2

See what's in common each time.

Solution: Git

2.Nested If statements and elif Statements

Flow Chart to understand the Nested IF

Example 1:

height = int(input("what is your height: ?"))

## We are using nested if statments to meet our conditions. 

if height > 120:
  print("you can ride the roller coaster")
  age = int(input("what is your age: ?"))
  if age == 18:
    print("you pay $5.")
  elif age >= 23:
    print("you pay $7.")
  else:
    print("you pay $12")
else:
  print("you cannot ride the roller coaster")

Quiz:

Instructions

Write a program that interprets the Body Mass Index (BMI) based on a user's weight and height.

It should tell them the interpretation of their BMI based on the BMI value.

• Under 18.5 they are underweight
• Over 18.5 but below 25 they have a normal weight
• Over 25 but below 30 they are slightly overweight
• Over 30 but below 35 they are obese
• Above 35 they are clinically obese.

The BMI is calculated by dividing a person's weight (in kg) by the square of their height (in m):

Warning you should round the result to the nearest whole number. The interpretation message needs to include the words in bold from the interpretations above. e.g. underweight, normal weight, overweight, obese, clinically obese.

Example Input

weight = 85

height = 1.75

Example Output

85 ÷ (1.75 x 1.75) = 27.755102040816325

Your BMI is 28, you are slightly overweight.

e.g. When you hit run, this is what should happen:

The testing code will check for print output that is formatted like one of the lines below:

"Your BMI is 18, you are underweight."
"Your BMI is 22, you have a normal weight."
"Your BMI is 28, you are slightly overweight."
"Your BMI is 33, you are obese."
"Your BMI is 40, you are clinically obese."

Hint

1. Try to use the exponent operator in your code.
2. Remember to round your result to the nearest whole number.
3. Make sure you include the words in bold from the interpretations.

3. Multiple If statements in succession

FlowChart: