Data Types

Boolean Logic

Boolean values store true or false decisions.

boolean A boolean is a value that is either `true` or `false`.

Boolean Logic

score
BoolLogic.cs
Replay: real traced execution (multi-file project)
using System;

class Program
{
    static void Main()
    {
        int score = 72;
        bool passed = score >= 70;
        string status = passed ? "pass" : "retry";

        Console.WriteLine($"score={score}");
        Console.WriteLine($"passed={passed}");
        Console.WriteLine($"status={status}");
    }
}

using System;

class Program
{
    static void Main()
    {
        int score = 45;
        bool passed = score >= 70;
        string status = passed ? "pass" : "retry";

        Console.WriteLine($"score={score}");
        Console.WriteLine($"passed={passed}");
        Console.WriteLine($"status={status}");
    }
}

using System;

class Program
{
    static void Main()
    {
        int score = 95;
        bool passed = score >= 70;
        string status = passed ? "pass" : "retry";

        Console.WriteLine($"score={score}");
        Console.WriteLine($"passed={passed}");
        Console.WriteLine($"status={status}");
    }
}

  1. score ← 72, passed ← True, status ← pass

    4{5    static void Main()6    {7        int score→ 72 = 72; //@score=45, 958        bool passed→ True = score72 >= 70;9        string status→ pass = passedTrue ? "pass" : "retry";1011        Console.WriteLine($"score={score72}");12        Console.WriteLine($"passed={passedTrue}");13        Console.WriteLine($"status={statuspass}");14    }
    outputscore=72
passed=True
status=pass

  1. score ← 45, passed ← False, status ← retry

    4{5    static void Main()6    {7        int score→ 45 = 45;8        bool passed→ False = score45 >= 70;9        string status→ retry = passedFalse ? "pass" : "retry";1011        Console.WriteLine($"score={score45}");12        Console.WriteLine($"passed={passedFalse}");13        Console.WriteLine($"status={statusretry}");14    }
    outputscore=45
passed=False
status=retry

  1. score ← 95, passed ← True, status ← pass

    4{5    static void Main()6    {7        int score→ 95 = 95;8        bool passed→ True = score95 >= 70;9        string status→ pass = passedTrue ? "pass" : "retry";1011        Console.WriteLine($"score={score95}");12        Console.WriteLine($"passed={passedTrue}");13        Console.WriteLine($"status={statuspass}");14    }
    outputscore=95
passed=True
status=pass

Follow the Decision

  1. score starts at 72.
  2. passed = score >= 70.
  3. 72 >= 70 is True.
  4. status becomes pass.
  5. The program prints score=72, passed=True, and status=pass. | score | passed | status | | --- | --- | --- | | 45 | False | retry | | 72 | True | pass | | 95 | True | pass |

Exercise: BoolLogic.cs

Reproduce status=pass, then use scores 45 and 95 to predict passed and status.