Strings

Concepts

• The string type str:

• The minimal string '',

• Indexing []

• Slicing [:]

• Membership: in(), not in())

• Inmutability property.

• The string methods:

• The str.format() method (String_Formattig/index).

• String traversal

Keywords

# size
     len()
# access and slice
     s[i], s[2:7], s[2:10:2]
# membership
     'a' in s, 'a' not in s, s1 in s,
# string methods
     s.count('a'), s.replace('a', 'A'), s.isalpha(), ...

Examples

Notes

• Strings
  • Un tipus de dades compost
  • Longitud
  • Llesques d’string
  • Comparació d’strings
  • L’operador in
  • Concatenació d’strings
  • Els strings són immutables
  • Mètodes d’strings

Slides

• slides

References

• Section 4 in. Prof. Dolors Ayala, 2020.

• How to Think Like a Computer Scientist: Learning with Python 2nd Edition.

• Mètodes de la classe **str**

Exercises

String Operations (operators, functions, methods)

• Currencies
• Electronic mail
• Eurovision
• Label
• Number plate
• Password
• Screw
• String classification
• String operations
• URL format

Exercises

String traversal using for either over the str or over range(len(str).

• Check alphabetical order
• Common characters
• Common prefix and suffix
• Consecutive letters
• Delete repeated characters
• Expressions
• Genetic sequence
• Letter count
• Pairs interchange
• Price increase
• Stars
• String construction