CSC 1060: Data Types and Variables

CSC 1060: Data Types and Variables

• Objectives: Understand and differentiate between fundamental data types in C++, declare & initialize variables, explain the data type concept, correctly declare variables in C++, apply appropriate naming conventions, and understand the importance of naming conventions.

• Agenda (Week 3):

  • Data Types & Variables
  • Declaration of a Variable
  • Naming Conventions for Variables
  • Coding Standards for Variables
  • Operators
  • Assignment
  • Solve Problem with Code
  • Type Conversation - and std::string
  • String common operators and functions
  • TODO & Resources for Help

• Fundamental Data Types in C++: int, float, double, char, bool

• String: Not a fundamental data type; part of C++ as std::string. Requires #include

• C++ Variable Declaration:

  • Data Type: Specifies the amount of storage and operations.
  • Name: Identifies the variable in a program; starts with a lowercase letter.
  • Value: Assigned into memory. Format: dataType name = value;

• C++ Rules & Standards (Variable Naming): Example variations: first-place, FirstPlace, first_place, 1stPlace, firstPlace, place, rankedlst

• C++ Declaring Variables: Examples provided as placeholders to be filled in:

  • = 0; // number of letters in word
  • = 0; // first name initial
  • = 0; // balance in bank account
  • = 0; // overall grade percent

• Assignment Statements:

  • Value assigned to variable leftVariable = rightValue;
  • Data types of left and right values should match for type safety.
  • Left variable must be declared before use (and cannot be a constant).
  • Right value can be an expression, formula, or another variable.

• Operators (C++):

  • Arithmetic: PEMMDAS ((), *, %, /, +, -)
  • Order of Operations (PEMDAS)
  • Exponent operator in C++
  • Modulus (%): remainder from division
  • Floating-point Division (/): 5/2.0
  • Integer Division (/): 5/2

• Solve Problem #1 with Code:

  • Single fair ticket: $8
  • Family pass: $25 more than half the ticket price. Calculate.

• Type Conversion (C++):

  • Implicit: Automatically occurs when copying to a compatible type.
  • Explicit (Casting): Needed for conversions involving data loss or different interpretations (e.g., int to float conversion).

• C++ std::string:

  • Sequence of characters; standardized data type.
  • No C-style strings (char[] or char*) – use std::string.
  • Stored contiguously in memory.
  • Indexed (0-based).

• std::string Object (Variable):

  • #include <string>
  • Create empty string: std::string name;
  • Create string from literal: std::string firstName = "Julie"; or std::string firstName("Julie");

• Common std::string Operations:

  • Assignment (=): assigns values
  • Concatenation (+): adds strings together
  • Subscript ([]): getting/setting characters at a particular index

• Common std::string Member Functions:

  • size() or length(): returns the number of characters in a string.
  • at(index): returns a character at a specified index.
  • find(char): searches for a character
  • substr(pos, len): selects part of the string.

• Common std::string Functions (Conversion):

  • std::to_string(var): converts various types (ints, floats, doubles) to a string.
  • std::stoi(str), std::stof(str), std::stod(str): converts strings to integers, floats, and doubles respectively.

• Solve Problem #2 with Code:

• Given "Red Rocks", reverse the string to "Rocks Red"

• Review Exercises: Complete multiple-choice questions 1-10.

• TODO: Complete week 2 content module in D2L to 100%.

• Post: Weekly discussion question and research solution to D2L

• Next: Week 3 prework starts Friday 1/26 8AM

• Help:

  • Student Office Hours: By appointment or drop-in.
  • Email: [email protected]
  • Tutoring:
    • On-campus tutoring: Link provided
    • 24/7 Online Tutoring: D2L content > Resources for Help

This quiz focuses on understanding fundamental data types and variables in C++. You'll learn how to declare and initialize variables, apply proper naming conventions, and understand the importance of these concepts in coding standards. Test your knowledge on data types like int, float, and std::string, and their usage in programming.