Strings continued

• Getting a Substring with Slice:

  • We can extract a substring (part of a string) from a string using a slice
  • We can define slice by using square brackets
    • start offset
    • end offset
    • step count
  • syntax:

  my_text = 'Hello How are you?'
  mytext[start_offset:end_offset:step]
  

  • Examples: 1
  • Examples: 2
    • Create a letters variable

    letters = "abcdefghijklmnopqrstuvwxyz"
    

    
    • Now print all the letters from m to z

    letters[12:]
    

    • Now try to print alternative letters from a to z i.e. ace…..

    letters[::2]
    

    • Now print all the letters in reverse

    letters[::-1]
    

    • Print letters from e to l

    letters[4:12]
    

    • Print letters from s to w

    letters[18:23]
    letters[18:-3]
    

    • Print every third character from d to y

    letters[3:25:3]
    letters[3:-2:3]
    

• Length function len() counts the characters in string

len(letters)

• Substitute by Using replace()

• Strip with strip():

• swapcase() function:

• Miscellaneous functions of string:

Program:

• Write a program in Python to find all the even numbers from 100 to 1000
• When to want to execute any lines of code repetitively then we need to use the looping constructs.
• The first looping construct is while
• Repeat with while:

while <condition>:
     <block>

• As long as condition is true the block of while executes
• Refer Here

Project Euler 1:

• Refer Here for the problem description
• Refer Here for the code done in the class.

Project Euler 6:

• Refer Here for the problem description
• Refer Here for the code created
• Fix for this problem is to increment index Refer Here