first commit

.editorconfig

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+# EditorConfig is awesome: https://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = false
+insert_final_newline = false

.gitignore

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+*.zip

build.nu

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+ls | where type == "dir" | sort-by name -n | get name | where $it != "common" |
+each { |folder|
+  cd $folder
+  if not ("common" | path exists) {
+    ln -s ../common ./common
+  }
+  if ("doc.typ" | path exists) {
+    typst compile doc.typ
+  }
+  let zip = ("../" + $folder + ".zip")
+  rm -f $zip
+  7z a $zip *
+}

common/common.typ

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+
+#let template(doc) = [
+  #set page(height: auto)
+  #show link: underline
+  #set quote(block: true)
+  #doc
+]
+
+#let embedClass(name: str) = {
+  show figure: set align(left)
+  show figure.caption: set align(center)
+  figure(caption: name, raw(read("../" + name + ".java"), lang:"java", block: true))
+}

week1/UseArgument.java

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+public class UseArgument {
+  public static void main(String[] args) {
+    System.out.print("Hi, ");
+    System.out.print(args[0]);
+    System.out.println(". How are you?");
+  }
+}

week1/UseThree.java

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+
+public class UseThree {
+  public static void main(String[] args) {
+    if (args.length != 3) {
+      System.out.println("Error: Program expects exactly three arguments");
+      return;
+    }
+    System.out.printf("Hi %s, %s and %s. How are you?%n", args[2], args[1], args[0]);
+  }
+}

week1/common

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+../common

week1/doc.typ

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+#import "./common/common.typ" : *
+
+#show: template
+
+= Week 1
+
+== Exercise 1.1.5
+
+#embedClass(name: "UseArgument")
+
+Describe what happens if you try to execute `UseArgument` with each of the
+following command lines:
+
+#set enum(numbering: "a.")
+
++ `java UseArgument java`
+
+  Prints `java` as the name: `Hi, java. How are you?`
+
++ `java UseArgument @!&^%`
+
+  This will return different results depending on the shell you're using.
+  If you pass those arguments directly as-is, it will just print `Hi, @!&^%. How are you?`.
+
+  If your shell uses any of these characters, not all arguments may be passed to the java program, you may get an error, or get no output.
+  For example, in a POSIX-compatible shell like bash, `&` is used as a delimiter to run programs asynchronously (return user control before the program finishes running), and otherwise acts as `;`. An error may be thrown due to `^%` not being a known command.
+  
++ `java UseArgument 1234`
+
+  Prints `Hi, 1234. How are you?`
+
++ `java UseArgument.java Bob`
+
+  Newer Java versions run `javac` if a `.java` file is provided as the class name to run, and then run the compiled bytecode.
+
++ `java UseArgument Alice Bob`
+
+  Arguments are whitespace delimited (in most shells), and only the first one is read in the program:
+  `Hi, Alice. How are you?`
+
+== Exercise 1.1.6
+
+Modify `UseArgument.java` to make a program `UseThree.java` that takes
+three names as command-line arguments and prints a proper sentence with the
+names in the rev
+
+#embedClass(name: "UseThree")

week2/RandomValues.java

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+import java.util.ArrayList;
+
+class RandomValues {
+  public static void main(String[] args) {
+    var numbers = new ArrayList<Double>(5);
+    for (var i = 0; i < 5; i++)
+      numbers.add(Math.random());
+    var min = 1.;
+    var max = 0.;
+    var sum = 0.;
+    for (var num : numbers) {
+      min = Math.min(num, min);
+      max = Math.max(num, max);
+      sum += num;
+    }
+
+    var avg = sum / numbers.size();
+
+    for (var num : numbers) {
+      System.out.printf("%f ", num);
+    }
+    System.out.println();
+    System.out.printf("Average: %f, Minimum: %f, Maximum: %f%n", avg, min, max);
+  }
+}

week2/WindChill.java

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+
+class WindChill {
+  public static void main(String[] args) {
+    if (args.length < 2) {
+      System.err.println("Usage: [temperature] [velocity]");
+      return;
+    }
+    var temperature = Double.parseDouble(args[0]);
+    var velocity = Double.parseDouble(args[1]);
+    if (Math.abs(temperature) > 50. || velocity > 120. || velocity < 3.) {
+      System.err.println("Values outside of allowed range.");
+      return;
+    }
+    var wind_chill = WindChill.calculateWindChill(temperature, velocity);
+    System.out.printf("The effective temperature is %fF.%n", wind_chill);
+  }
+
+  public static double calculateWindChill(double T, double v) {
+    return 35.74 + (0.6215 * T) + (0.4275 * T - 35.75) * Math.pow(v, 0.16);
+  }
+}

week2/common

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+../common

week2/doc.typ

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+#import "./common/common.typ" : *
+
+#show: template
+
+= Week 2
+
+== Exercise 1.2.25
+
+_Wind chill_. Given the temperature $T$ (in degrees Fahrenheit)
+and the wind speed v (in miles per hour), the National Weather Service
+defines the effective temperature (the wind chill) as follows:
+
+$w = 35.74 + 0.6215 T + (0.4275 T - 35.75) v^0.16$
+
+Write a program that takes two double command-line arguments temperature
+and velocity and prints the wind chill. Use ```java Math.pow(a, b)``` to
+compute $a^b$. Note:
+The formula is not valid if $T$ is larger than $50$ in absolute value or
+if v is larger than $120$ or less than $3$ (you may assume that the values
+you get are in that range).
+
+#embedClass(name: "WindChill")
+
+== Exercise 1.2.30
+
+_Uniform random numbers_. Write a program that prints five uniform random
+numbers between $0$ and $1$, their average value, and their minimum and
+maximum values. Use ```java Math.random()```, ```java Math.min()```, and
+```java Math.max()```.
+
+#embedClass(name: "RandomValues")

week3/Gambler.java

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+public class Gambler {
+  public static void main(String[] args) {
+    // Run trials experiments that start with
+    // $stake and terminate on $0 or $goal.
+    int stake = Integer.parseInt(args[0]);
+    int goal = Integer.parseInt(args[1]);
+    int trials = Integer.parseInt(args[2]);
+    double probability = Double.parseDouble(args[3]);
+    int bets = 0;
+    int wins = 0;
+    for (int t = 0; t < trials; t++) {
+      // Run one experiment.
+      int cash = stake;
+      while (cash > 0 && cash < goal) {
+        // Simulate one bet.
+        bets++;
+        if (Math.random() < probability)
+          cash++;
+        else
+          cash--;
+      }
+      // Cash is either 0 (ruin) or $goal (win).
+      if (cash == goal)
+        wins++;
+    }
+    System.out.println(100 * wins / trials + "% wins");
+    System.out.println("Avg # bets: " + bets / trials);
+  }
+}

week3/GamblerPlot.java

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+public class GamblerPlot {
+  public static void main(String[] args) {
+    // Run trials experiments that start with
+    // $stake and terminate on $0 or $goal.
+    int stake = Integer.parseInt(args[0]);
+    int goal = Integer.parseInt(args[1]);
+    double probability = 0.5;
+    int bets = 0;
+    
+    // Run one experiment.
+    int cash = stake;
+    while (cash > 0 && cash < goal) {
+      // Simulate one bet.
+      bets++;
+      if (Math.random() < probability)
+        cash++;
+      else
+        cash--;
+
+      GamblerPlot.printCash(cash);
+    }
+
+    boolean won = cash == goal;
+    String wonText = won ? "Won" : "Lost";
+
+    System.out.println();
+    System.out.printf("%s after %s bets", wonText, bets);
+  }
+
+  public static void printCash(int cash) {
+    for(int i = 0; i < cash; i++) {
+      System.out.print("*");
+    }
+    System.out.println();
+  }
+}

week3/RollLoadedDie.java

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+public class RollLoadedDie {
+  public static void main(String[] args) {
+    double rand8 = Math.random() * 8.;
+    // floor returns double. Round gives long for double input, so conversion needed
+    int random = (int)(Math.round(Math.floor(rand8)) + 1);
+    // 1 - 8 to 1 - 6, with 6 receiving the probabilities of 7 - 8
+    random = Math.min(random, 6);
+    System.out.println(random);
+  }
+}

week3/common

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+../common

week3/doc.typ

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+#import "./common/common.typ" : *
+
+#show: template
+
+= Week 3
+
+== Exercise 1.3.5
+
+Write a program `RollLoadedDie` that prints the result of rolling
+a loaded die such that the probability of getting a $1$, $2$, $3$, $4$,
+or $5$ is $1/8$ and the probability of getting a $6$ is $3/8$.
+
+#embedClass(name: "RollLoadedDie")
+
+== Exercise 1.3.24
+
+Write a program `GamblerPlot` that traces a gambler's ruin simulation
+by printing a line after each bet in which one asterisk corresponds
+to each dollar held by the gambler.
+
+#embedClass(name: "GamblerPlot")
+
+== Exercise 1.3.25
+
+Modify `Gambler` to take an extra command-line argument that specifies
+the (fixed) probability that the gambler wins each bet. Use your program
+to try to learn how this probability affects the chance of winning and the
+expected number of bets. Try a value of $p$ close to $0.5$ (say, $0.48$).
+
+#embedClass(name: "Gambler")

week4/Card.java

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+public class Card {
+  public static final String CLUBS = "♣";
+  public static final String DIAMONDS = "♦";
+  public static final String HEARTS = "♥";
+  public static final String SPADES = "♠";
+
+  public enum Suit {
+    Clubs,
+    Diamonds,
+    Hearts,
+    Spades;
+
+    public String sprint() {
+      switch(this) {
+        case Clubs: return Card.CLUBS;
+        case Diamonds: return Card.DIAMONDS;
+        case Hearts: return Card.HEARTS;
+        case Spades: return Card.SPADES;
+      }
+      throw new NullPointerException();
+    }
+  }
+
+  public Suit suit;
+  public int value;
+
+  public Card(Suit suit, int value) {
+    this.suit = suit;
+    this.value = value;
+  }
+
+  public static Card fromNumbers(int suit, int value) {
+    return new Card(Suit.values()[suit], value);
+  }
+
+  public String sprintValue() {
+    if(this.value == 1) {
+      return "A";
+    } else if(this.value == 11) {
+      return "J";
+    } else if(this.value == 12) {
+      return "Q";
+    } else if(this.value == 13) {
+      return "K";
+    } else if(this.value == 10) {
+      return "⒑";
+    }
+    return Integer.toString(this.value);
+  }
+
+  public String sprintCard() {
+    var output = "";
+    var value = this.sprintValue();
+    var suit = this.suit.sprint();
+    
+    output += value;
+    
+    if(this.value > 10) {
+      output += "   ";
+    } else {
+      output += this.value >= 4 ? suit : " ";
+      output += this.value < 4 && this.value > 1 ? suit : " ";
+      output += this.value >= 4 ? suit : " ";
+    }
+    output += value;
+    output += "\n";
+
+    if(this.value > 10) {
+      output += suit + "   " + suit + "\n";
+      output += suit + "   " + suit + "\n";
+    } else {
+      output += " ";
+      output += this.value >= 6 ? suit : " ";
+      output += this.value % 2 == 1 || this.value >= 8 ? suit : " ";
+      output += this.value >= 6 ? suit : " ";
+      output += " ";
+      output += "\n";
+  
+      
+      output += " ";
+      output += this.value >= 9 ? suit : " ";
+      output += this.value == 8 || this.value == 10 ? suit : " ";
+      output += this.value >= 9 ? suit : " ";
+      output += " ";
+      output += "\n";
+    }
+
+    
+    output += value;
+    
+    if(this.value > 10) {
+      output += "   ";
+    } else {
+      output += this.value >= 4 ? suit : " ";
+      output += this.value < 4 && this.value > 1 ? suit : " ";
+      output += this.value >= 4 ? suit : " ";
+    }
+    output += value;
+    output += "\n";
+
+    return output;
+  }
+
+  public static String sprintCards(Card[] cards) {
+    String[] output = { "", "", "", "" };
+
+    for(var i = 0; i < cards.length; i++) {
+      var cardstr = cards[i].sprintCard().split("\n");
+      for(var x = 0; x < cardstr.length; x++) {
+        output[x] += cardstr[x] + " ";
+      }
+    }
+
+    var outputstr = "";
+    for(var i = 0; i < output.length; i++) {
+      outputstr += output[i] + "\n";
+    }
+    return outputstr;
+  }
+}

week4/Deal.java

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+import java.util.Random;
+
+public class Deal {
+  public static void main(String[] args) {
+    int handCount = Integer.parseInt(args[0]);
+    if(handCount > 10) {
+      System.err.println("Too many hands! Maximum is 10.\njava Deal [hands]");
+    }
+
+    Card[] deck = new Card[52];
+    for(var i = 0; i < 52; i++) {
+      var value = (i % 13) + 1;
+      var suit = i / 13;
+      deck[i] = Card.fromNumbers(suit, value);
+    }
+    
+    Random random = new Random();
+    for(var i = 0; i < deck.length; i++) {
+      var second = random.nextInt(deck.length);
+      var a = deck[i];
+      deck[i] = deck[second];
+      deck[second] = a;
+    }
+
+    for(var handNumber = 0; handNumber < handCount; handNumber++) {
+      var offset = handNumber * 5; 
+      Card[] hand = { deck[offset], deck[offset+1], deck[offset+2], deck[offset+3], deck[offset+4] };
+      System.out.println(Card.sprintCards(hand));
+    }
+  }
+}

week4/common

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+../common

week4/doc.typ

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+#import "./common/common.typ" : *
+
+#show: template
+
+= Week 4
+
+== Exercise 1.4.10
+
+Write a program `Deal` that takes an integer command-line argument `n` and
+prints `n` poker hands (five cards each) from a shuffled deck, separated by blank lines.
+
+#embedClass(name: "Deal")
+
+#embedClass(name: "Card")
+
+== Exercise 1.4.14
+
+Write a code fragment to print the transposition (rows and columns exchanged) of a square two-dimensional array.
+For the example spreadsheet array in the text, you code would print the following:
+
+```
+99 98 92 94 99 90 76 92 97 89
+85 57 77 32 34 46 59 66 71 29
+98 78 76 11 22 54 88 89 24 38
+```