labs

labs/lab3/LuckyNumbers.java

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+// **************************************************
+// LuckyNumbers.java
+//
+// To generate three random "lucky" numbers
+// **************************************************
+import java.util.Random;
+public class LuckyNumbers
+{
+public static void main (String[] args)
+{
+Random generator = new Random();
+int lucky1, lucky2, lucky3;
+// Generate lucky1 (a random integer between 50 and 79) using the
+// nextInt method (with no parameter)
+lucky1 = generator.nextInt(30) + 50;
+// Generate lucky2 (a random integer between 90 and 100) using the
+// nextInt method with an integer parameter
+lucky2 = generator.nextInt(11) + 90;
+// Generate lucky3 (a random integer between 11 and 30) using nextFloat
+lucky3 = (int) (generator.nextFloat() * 20) + 11;
+System.out.println ("Your lucky numbers are " + lucky1 + ", " + lucky2
++ ", and " + lucky3);
+}
+}

labs/lab3/RightTriangle.java

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+// *******************************************************************
+// RightTriangle.java
+//
+// Compute the length of the hypotenuse of a right triangle
+// given the lengths of the sides
+// *******************************************************************
+import java.util.Scanner;
+public class RightTriangle
+{
+public static void main (String[] args)
+{
+double side1, side2; // lengths of the sides of a right triangle
+double hypotenuse; // length of the hypotenuse
+Scanner scan = new Scanner(System.in);
+// Get the lengths of the sides as input
+System.out.print ("Please enter the lengths of the two sides of " +
+"a right triangle (separate by a blank space): ");
+side1 = scan.nextDouble();
+side2 = scan.nextDouble();
+// Compute the length of the hypotenuse
+hypotenuse = Math.sqrt(Math.pow(side1, 2) + Math.pow(side2, 2));
+// Print the result
+System.out.println ("Length of the hypotenuse: " + hypotenuse);
+}
+}

labs/lab3/StringManips.java

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+// ***************************************************************
+// StringManips.java
+//
+// Test several methods for manipulating String objects
+// ***************************************************************
+import java.util.Scanner;
+public class StringManips
+{
+public static void main (String[] args)
+{
+String phrase = new String ("This is a String test.");
+int phraseLength; // number of characters in the phrase String
+int middleIndex; // index of the middle character in the String
+String firstHalf; // first half of the phrase String
+String secondHalf; // second half of the phrase String
+String switchedPhrase; // a new phrase with original halves switched
+String middle3;
+String city;
+String state;
+Scanner scan = new Scanner(System.in);
+
+System.out.println("Enter your city!");
+city = scan.nextLine();
+System.out.println("Enter your state!");
+state = scan.nextLine();
+String newString = state.toUpperCase() + city.toLowerCase() + state.toUpperCase();
+// compute the length and middle index of the phrase
+phraseLength = phrase.length();
+middleIndex = phraseLength / 2;
+// get the substring for each half of the phrase
+firstHalf = phrase.substring(0,middleIndex);
+secondHalf = phrase.substring(middleIndex, phraseLength);
+// concatenate the firstHalf at the end of the secondHalf
+switchedPhrase = secondHalf.concat(firstHalf);
+switchedPhrase = switchedPhrase.replace(" ", "*");
+
+middle3 = phrase.substring(middleIndex - 1, middleIndex + 2);
+// print information about the phrase
+System.out.println();
+System.out.println ("Original phrase: " + phrase);
+System.out.println ("Length of the phrase: " + phraseLength +
+" characters");
+System.out.println ("Index of the middle: " + middleIndex);
+System.out.println ("Character at the middle index: " +
+phrase.charAt(middleIndex));
+System.out.println ("Switched phrase: " + switchedPhrase);
+System.out.println();
+System.out.println(newString);
+}
+}

labs/lab3/StringPlay.java

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+// **************************************************
+// StringPlay.java
+//
+// Play with String objects
+// **************************************************
+public class StringPlay
+{
+public static void main (String[] args)
+{
+String college = new String ("PoDunk College");
+String town = new String ("Anytown, USA"); // part (a)
+int stringLength;
+String change1, change2, change3;
+stringLength = college.length(); // part (b)
+System.out.println (college + " contains " + stringLength + " characters.");
+change1 = college.toUpperCase(); // part (c)
+change2 = change1.replace("O","*"); // part (d)
+change3 = college.concat(", ").concat(town); // part (e)
+System.out.println ("The final string is " + change3);
+}
+}