Methods

src/main/java/com/amigoscode/_1_beginners/_1_thebasics/MethodExercises.java

@@ -11,43 +11,81 @@ public class MethodExercises {
     // TODO: 1 - Create a method called greet that takes a String parameter 'name'
     // and prints "Hello, {name}!"
     // Hint: public static void greet(String name) { ... }
-
+    public static void greet(String name) {
+        System.out.printf("Hello %s",name);
+        System.out.println();
+    }
 
     // TODO: 2 - Create a method called add that takes two int parameters (a, b)
     // and returns their sum
     // Hint: public static int add(int a, int b) { ... }
+    public static int add(int a, int b) {
+        return a + b;
+    }
 
 
     // TODO: 3 - Create a method called isEven that takes an int parameter 'number'
     // and returns true if the number is even, false otherwise
     // Hint: Use the modulus operator (%)
-
+    public static boolean isEven(int number) {
+        return number % 2 == 0;
+    }
 
     // TODO: 4 - Create a method called max that takes two int parameters (a, b)
     // and returns the larger of the two
     // Hint: Use an if statement or the ternary operator
-
+    public static int max(int a, int b) {
+        return Math.max(a, b);
+    }
 
     // TODO: 5 - Create a method called factorial that takes an int parameter 'n'
     // and returns n! (n factorial) using a loop
     // Hint: 5! = 5 * 4 * 3 * 2 * 1 = 120. Use a long return type for larger values.
+    public static int factorial(int n) {
+        int factorialPlaceholder = 1;
+        for (int num = 1; num <= n; num++) {
+            factorialPlaceholder *= num;
+        }
+        return factorialPlaceholder;
+    }
 
 
     // TODO: 6 - Create two overloaded methods called multiply:
     //   - One that takes 2 int parameters and returns their product
     //   - One that takes 3 int parameters and returns their product
     // Overloading means having multiple methods with the same name but different parameters.
+    public static int multiply(int a, int b) {
+        return a * b;
+    }
+
+    public static int multiply(int a, int b, int c) {
+        return a * b * c;
+    }
 
 
     public static void main(String[] args) {
 
         // TODO: 7 - Call all the methods above and print their results
         // - Call greet with your name
+        greet("Jose");
         // - Call add with two numbers and print the result
+        int result = add(6, 7);
+        System.out.println(result);
         // - Call isEven with a number and print whether it is even
+        boolean isEvenResult = isEven(5);
+        System.out.println(isEvenResult);
         // - Call max with two numbers and print the larger one
+        int maxNumber = max(6, 9);
+        System.out.println(maxNumber);
         // - Call factorial with 5 and print the result
+        int factorialRes = factorial(7);
+        System.out.println(factorialRes);
         // - Call both multiply methods and print their results
+        int multiply1 = multiply(5, 5);
+        int multiply2 = multiply(5, 5, 5);
+
+        System.out.println("multiply1 result: " + multiply1);
+        System.out.println("multiply2 result: " + multiply2);
 
     }
 }

src/main/java/com/amigoscode/_1_beginners/_1_thebasics/Operators.java

@@ -13,40 +13,90 @@ public static void main(String[] args) {
         // TODO: 1 - Use arithmetic operators (+, -, *, /) on two int variables and print the results
         // Declare two int variables (e.g., a = 10, b = 3)
         // Print the result of a + b, a - b, a * b, and a / b
+        System.out.println("TODO 1");
+        int num1 = 10;
+        int num2 = 3;
 
+        System.out.println("Addition: " + (num1 + num2));
+        System.out.println("Subtraction: " + (num1 - num2));
+        System.out.println("Multiplication: " + (num1 * num2));
+        System.out.println("Division: " + (num1 /+ num2));
+        System.out.println();
 
         // TODO: 2 - Use the modulus operator (%) to check if a number is even
         // Declare an int variable called number with any value.
         // Print the result of number % 2
         // Print whether the number is even (result is 0) or odd (result is 1)
-
+        System.out.println("TODO 2");
+        System.out.println("------------------------");
+        int variable = 78;
+        int isEven = variable % 2 == 0 ? 0 : 1;
+        System.out.println(isEven);
 
         // TODO: 3 - Use increment (++) and decrement (--) operators
         // Declare an int variable called counter, set it to 5
         // Use counter++ and print the result, then use counter-- and print the result
-
+        System.out.println("TODO 3");
+        System.out.println("------------------------");
+        int counter = 5;
+        counter++;
+        System.out.println(counter);
+        counter--;
+        System.out.println(counter);
 
         // TODO: 4 - Use compound assignment operators (+=, -=, *=)
         // Declare an int variable called score, set it to 10
         // Use +=, -=, and *= on score, printing after each operation
+        System.out.println("TODO 4");
+        System.out.println("------------------------");
+        int score = 10;
+        score += 5;
+        System.out.println(score);
+        score -= 5;
+        System.out.println(score);
+        score *= 5;
+        System.out.println(score);
+
 
 
         // TODO: 5 - Use comparison operators (==, !=, >, <, >=, <=) and print the boolean results
         // Declare two int variables (e.g., x = 5, y = 10)
         // Print the result of each comparison, e.g.: System.out.println("x == y: " + (x == y));
+        System.out.println("TODO 5");
+        System.out.println("------------------------");
+        int x = 20;
+        int y = 40;
+        System.out.println("x == y: " + ( x == y));
+        System.out.println("x >= y: " + (x >= y));
+        System.out.println("x <= y: " + (x <= y));
+        System.out.println("x > y: " + (x > y));
+        System.out.println("x < y: " + (x < y));
+        System.out.println("x != y: " + (x != y));
 
 
         // TODO: 6 - Use logical operators (&&, ||, !) to combine conditions
         // Declare two boolean variables (e.g., hasLicense = true, hasInsurance = false)
         // Print the result of: hasLicense && hasInsurance
         // Print the result of: hasLicense || hasInsurance
         // Print the result of: !hasLicense
+        System.out.println("TODO 6");
+        System.out.println("------------------------");
+        boolean hasLicense = true;
+        boolean hasInsurance = false;
+        System.out.println("hasLicense && hasInsurance: " + (hasLicense && hasInsurance));
+        System.out.println("hasLicense || hasInsurance: " + (hasLicense || hasInsurance));
+        System.out.println("!hasLicense: " + (!hasLicense));
 
 
         // TODO: 7 - Use the ternary operator to assign "adult" or "minor" based on age
         // Declare an int variable called age with any value
         // Use the ternary operator: String status = (condition) ? "adult" : "minor";
         // Print the status
+        System.out.println("TODO 6");
+        System.out.println("------------------------");
+        int age = 36;
+        String status = age >= 18 ? "adult" : "minor";
+        System.out.println("Are you an adult?: " + status);
 
     }
 }

src/main/java/com/amigoscode/_1_beginners/_1_thebasics/TypeCasting.java

@@ -14,31 +14,62 @@ public static void main(String[] args) {
         // TODO: 1 - Widen an int to a double (implicit casting)
         // Declare an int variable with any value, then assign it to a double variable.
         // Print both variables to see the result.
-
+        System.out.println("Widen an int to a double (implicit casting)");
+        int number = 50;
+        double numberCastedDouble = number;
+        System.out.println("number: " + number);
+        System.out.println("numberDouble: " + numberCastedDouble);
 
         // TODO: 2 - Narrow a double to an int (explicit casting)
         // Declare a double variable (e.g., 9.78), then cast it to an int.
         // Print both variables to see what happens to the decimal part.
-
+        System.out.println("---------------------------------------------");
+        System.out.println("Narrow a double to an int (explicit casting)");
+        double todoTwoDouble = 9.78;
+        int todoTwoInt = (int) todoTwoDouble;
+        System.out.println("todoTwoDouble: " + todoTwoDouble);
+        System.out.println("todoTwoInt: " + todoTwoInt);
 
         // TODO: 3 - Cast an int to a char to get the character it represents
         // Hint: int value 65 corresponds to 'A' in ASCII
         // Print the resulting char.
+        System.out.println("---------------------------------------------");
+        System.out.println("Cast an int to a char to get the character it represents");
+        int todoThreeInt = 65;
+        char todoThreeChar = (char) todoThreeInt;
+        System.out.println("todoThreeInt: " + todoThreeInt);
+        System.out.println("todoThreeChar: " + todoThreeChar);
 
 
         // TODO: 4 - Cast a char to an int to get its ASCII value
         // Hint: char 'Z' has an ASCII value of 90
         // Print the resulting int.
+        System.out.println("---------------------------------------------");
+        System.out.println("Cast a char to an int to get its ASCII value");
+        char todoFourChar = 'Z';
+        int todoFourInt = todoFourChar;
+        System.out.println("todoFourChar: " + todoFourChar);
+        System.out.println("todoFourInt: " + todoFourInt);
+
 
 
         // TODO: 5 - Convert a String "42" to an int using Integer.parseInt()
         // Declare a String variable with the value "42", then parse it to an int.
         // Print the result.
+        System.out.println("---------------------------------------------");
+        System.out.println("Convert a String \"42\" to an int using Integer.parseInt()");
+        String todoFiveString = "42";
+        System.out.println(Integer.parseInt(todoFiveString));
 
 
         // TODO: 6 - Convert an int 42 to a String using String.valueOf()
         // Declare an int variable with the value 42, then convert it to a String.
         // Print the result.
+        System.out.println("---------------------------------------------");
+        System.out.println("Convert an int 42 to a String using String.valueOf()");
+        int todoSixInt = 42;
+        String todoSixIntString = String.valueOf(todoSixInt);
+        System.out.println(todoSixIntString);
 
     }
 }

src/main/java/com/amigoscode/_1_beginners/_1_thebasics/Variables.java

@@ -11,27 +11,33 @@ public class Variables {
     public static void main(String[] args) {
 
         // TODO: 1 - Declare an int variable called age and assign it the value 25
-
+        int age = 25;
 
         // TODO: 2 - Declare a double variable called price and assign it the value 9.99
-
+        double price = 9.99;
 
         // TODO: 3 - Declare a boolean variable called isJavaFun and assign it the value true
-
+        boolean isJavaFun = true;
 
         // TODO: 4 - Declare a String variable called name and assign it your name
-
+        String name = "Jose";
 
         // TODO: 5 - Declare a char variable called grade and assign it the value 'A'
-
+        char grade = 'A';
 
         // TODO: 6 - Print all the variables above using System.out.println
         // Hint: You can print each variable on its own line, e.g.:
         //   System.out.println("Age: " + age);
-
+        System.out.println("Age: " + age);
+        System.out.println("Price: " + price);
+        System.out.println("isJavaFun: " + isJavaFun);
+        System.out.println("Name: " + name);
+        System.out.println("Grade: " + grade);
 
         // TODO: 7 - Declare a final (constant) variable called MAX_SCORE, set it to 100, and print it
         // Hint: Use the 'final' keyword before the type to make a constant
+        final int MAX_SCORE = 100;
+        System.out.println("MAX_SCORE: " + MAX_SCORE);
 
     }
 }