PL101FINALS

• In computer programming, loops are used to repeat a block of code.
• There are 2 types of loops in Python:

  for loop, while loop
• In Python, the for loop is used to run a block of code for a certain number of times. It is

  used to iterate over any sequences such as list, tuple, string, etc.
• The syntax of the for loop is:

  for val in sequence:

  # statement(s)
• What's the output?

  languages = ['Swift,'Python','Go','JavaScript']

  for language in languages:

  print(language)

  Swift

  Python

  Go

  JavaScript
• A range is a series of values between two numeric intervals.
• We use Python's built-in function range() to define a range of values.
• values = range(4)

  for i in values:

  print(i)

  OUTPUT:

  0

  1

  2

  3
• digits = [0, 1, 5]

  for i in digits:

  print(i)

  else:

  print("No items left.")

  OUTPUT:

  0

  1

  5

  No items left.
• 
  

  When we have a for loop inside another for loop, it’s called a nested for loop.
• The break statement is used to exit the for loop prematurely. It’s used to break the for loop when a specific condition is met.
• We can use continue statements inside a for loop to skip the execution of the for loop body for a specific condition.
• A while loop implements the repeated execution of code based on a given Boolean condition.

  The code that is in a while block will execute as long as the while statement evaluates to True.
• You can think of the while loop as a repeating conditional statement.
• As opposed to for loops that execute a certain number of times, while loops are conditionally

  based, so you don’t need to know how many times to repeat the code going
• Python while loop is used to run a specific code until a certain condition is met.
• The for loop is usually used when the number of iterations is known.
• while loop is usually used when the number of iterations is unknown.
• An infinite loop occurs when a program keeps executing within one loop, never leaving it.
• and and or are logical operators used to combine multiple conditions in Boolean

  expressions.
• The and operator returns True if both of the conditions it connects are True; otherwise, it

  returns False.
• The or operator returns True if at least one of the conditions it connects is True; it returns False

  only if both conditions are False.
• The break statement is used to terminate the loop immediately when it is encountered.
• We can use the break statement with for loop to terminate the loop when a certain condition is

  met.
• The continue statement is used to skip the current iteration of the loop and the control flow of

  the program goes to the next iteration.
• In Python programming, the pass statement is a null statement which can be used as a

  placeholder for future code.
• 1. A function is a block of code that performs a specific task when the function is

  called (invoked).
• A parameter is actually a variable, but there are two important factors that make

  parameters different and special
• step parameter It tells the range function how many numbers to skip between each count.