Cornelius Eanes's Programming Portal
Assignments (Strings)
[32] Making Decisions with If Statements
Goal: Learn about how to create If statements.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: Making Decisions with If Statements
/// File Name: AgeMessages.java
/// Date Finished: Oct 08, 2015
import java.util.Scanner;
public class AgeMessages {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int age;
System.out.println("How old are you?");
age = input.nextInt();
if (age < 13) {
System.out.println("You are too young to create a Facebook account.");
}
if (age < 16) {
System.out.println("You are too young to get a driver's license.");
}
if (age < 21) {
System.out.println("You are too young to drink alcohol.");
}
if (age < 35) {
System.out.println("You are too young to run for president of the USA.");
}
}
}
Output
[33] What If?
Goal: Figure out what If statements do.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: What If?
/// File Name: WhatIf.java
/// Date Finished: Oct 08, 2015
public class WhatIf {
public static void main(String[] args) {
int people = 20;
int cats = people;
int dogs = 15;
if (people < cats) {
System.out.println("There are too many cats!");
}
if (people > cats) {
System.out.println("There are a normal amount of cats.");
}
if (people < dogs) {
System.out.println("There are too many dogs!");
}
if (people > dogs) {
System.out.println("There are a normal amount of dogs.");
}
dogs += 5;
if (people >= dogs) {
System.out.println("People are greater than or equal to dogs.");
}
if (people <= dogs) {
System.out.println("People are less than or equal to dogs.");
}
if (people == dogs) {
System.out.println("People are dogs.");
}
// The If Statement runs the code inside of the braces if the passed
// conditional evaluates to true.
// The braces determines what code is ran when the conditional does evaluate
// to true. The ending brace signifies the end of the code block.
}
}
Output
[34] How Old are You?
Goal: Create a little program using If statements.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: How Old are You?
/// File Name: HowOldAreYou.java
/// Date Finished: Oct 08, 2015
import java.util.Scanner;
public class HowOldAreYou {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String name;
int age;
System.out.print("Hello, what's your name? ");
name = input.nextLine();
System.out.print("OK, " + name + ", how old are you? ");
age = input.nextInt();
if (age < 16) {
System.out.println("You can't drive.");
}
if (age < 18) {
System.out.println("You can't vote.");
}
if (age < 25) {
System.out.println("You can't rent a car.");
}
if (age >= 25) {
System.out.println("You can do anything that's legal.");
}
}
}
Output
[35] Else and If
Goal: Learn about the Else-If and Else statements.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: Else and If
/// File Name: ElseAndIf.java
/// Date Finished: Oct 08, 2015
public class ElseAndIf {
public static void main(String[] args) {
int people = 30;
int cars = 40;
int buses = 15;
if (cars > people) {
System.out.println("We should take the cars.");
} else if (cars < people) {
System.out.println("We should not take the cars.");
} else {
System.out.println("We can't decide.");
}
if (buses > cars) {
System.out.println("That's too many buses.");
}
if (buses < cars) {
System.out.println("Maybe we could take the buses.");
} else {
System.out.println("We still can't decide.");
}
if (people > buses) {
System.out.println("All right, let's just take the buses.");
} else {
System.out.println("Fine, let's stay home then.");
}
// Else-If statements will be checked if the preceding If/Else-If statement
// evaluates to false.
// If none of the If nor Else-If Statement conditionals evaluates to true,
// then whatever's in the Else code block (if there is one) is ran.
// Removing an 'else' from an Else-If statement will guarantee that it will
// be checked. As mentioned earlier, Else-If statements only get checked when
// the preceding statements evaluate to false.
}
}
Output
[36] Weekday Name
Goal: Print out what day of the week it is based on the given input.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: Weekday Name
/// File Name: WeekdayName.java
/// Date Finished: Oct 14, 2015
import java.util.GregorianCalendar;
public class WeekdayName {
public static String getWeekdayName(int weekday) {
String result;
if (weekday == 1) {
result = "Sunday";
} else if (weekday == 2) {
result = "Monday";
} else if (weekday == 3) {
result = "Tuesday";
} else if (weekday == 4) {
result = "Wednesday";
} else if (weekday == 5) {
result = "Thursday";
} else if (weekday == 6) {
result = "Friday";
} else if (weekday == 7) {
result = "Saturday";
} else {
result = "error";
}
return result;
}
public static void main( String[] args ) {
System.out.println("Weekday 1: " + getWeekdayName(1));
System.out.println("Weekday 2: " + getWeekdayName(2));
System.out.println("Weekday 3: " + getWeekdayName(3));
System.out.println("Weekday 4: " + getWeekdayName(4));
System.out.println("Weekday 5: " + getWeekdayName(5));
System.out.println("Weekday 6: " + getWeekdayName(6));
System.out.println("Weekday 7: " + getWeekdayName(7));
System.out.println("Weekday 0: " + getWeekdayName(0));
System.out.println();
System.out.println("Weekday 43: " + getWeekdayName(43));
System.out.println("Weekday 17: " + getWeekdayName(17));
System.out.println("Weekday -1: " + getWeekdayName(-1));
GregorianCalendar cal = new GregorianCalendar();
int dow = cal.get(GregorianCalendar.DAY_OF_WEEK);
System.out.println("\nToday is a " + getWeekdayName(dow) + "!");
}
}
Output
[37] How Old are You, Specifically?
Goal: Condense the output from Assignment 34 into a single line.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: How Old are You, Specifically?
/// File Name: HowOld2.java
/// Date Finished: Oct 14, 2015
import java.util.Scanner;
public class HowOld2 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String name;
int age;
System.out.print("Hello, what's your name again? ");
name = input.nextLine();
System.out.print("Okay, " + name + ", how old are you? ");
age = input.nextInt();
if (age < 16) {
System.out.println("You can't drive.");
} else if (age < 18) {
System.out.println("You can drive, but not vote.");
} else if (age < 24) {
System.out.println("You can vote, but not rent a car.");
} else {
System.out.println("You can do pretty much anything.");
}
}
}
Output
[38] Space Boxing
Goal: Calculate your weight on a specified planet.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: Space Boxing
/// File Name: SpaceBoxing.java
/// Date Finished: Oct 14, 2015
import java.util.Scanner;
public class SpaceBoxing {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
double weight;
int planetId;
System.out.print("Please enter your current Earth weight: ");
weight = input.nextDouble();
System.out.println("I have information for the following planets:");
System.out.println("\t1. Venus 2. Mars 3. Jupiter");
System.out.println("\t4. Saturn 5. Uranus 6. Neptune");
System.out.println();
System.out.print("Which planet are you visiting? ");
planetId = input.nextInt();
if (planetId == 1) {
weight *= 0.78;
} else if (planetId == 2) {
weight *= 0.39;
} else if (planetId == 3) {
weight *= 2.65;
} else if (planetId == 4) {
weight *= 1.17;
} else if (planetId == 5) {
weight *= 1.05;
} else if (planetId == 6) {
weight *= 1.23;
} else {
System.out.println("ERROR: Invalid planet ID: " + planetId);
weight = 0;
}
System.out.println("Your weight would be " + weight + " [lbs] on that planet.");
}
}
Output
[39] A Little Quiz
Goal: Quiz and score the user based on their answers.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: A Little Quiz
/// File Name: ALittleQuiz.java
/// Date Finished: Oct 14, 2015
import java.util.Scanner;
public class ALittleQuiz {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int choice1, choice2, choice3, numCorrect = 0;
System.out.println("Q1) What do you do to properly compare two strings together?");
System.out.println("\t1) Use the reference equals (==) operator.");
System.out.println("\t2) Use the .equals(String) method from one string.");
System.out.print("\n> ");
choice1 = input.nextInt();
System.out.println();
if (choice1 == 2) {
System.out.println("That's correct!");
numCorrect++;
} else {
System.out.println("Sorry, that's incorrect!");
}
System.out.println();
System.out.println("Q2) How many terms can a U.S. president run for, and for how long?");
System.out.println("\t1) 4 terms / 2 years");
System.out.println("\t2) 2 terms / 6 years");
System.out.println("\t3) 2 terms / 4 years");
System.out.print("\n> ");
choice2 = input.nextInt();
System.out.println();
if (choice2 == 3) {
System.out.println("That's correct!");
numCorrect++;
} else {
System.out.println("Sorry, that's incorrect!");
}
System.out.println();
System.out.println("Q3) What is the most common type of market in the United States today?");
System.out.println("\t1) Differentiated Oligopoly");
System.out.println("\t2) Pure Oligopoly");
System.out.println("\t3) Differentiated Monopolistic");
System.out.println("\t4) Pure Monopolistic");
System.out.println("\t5) Monopoly");
System.out.print("\n> ");
choice3 = input.nextInt();
System.out.println();
if (choice3 == 3) {
System.out.println("That's correct!");
numCorrect++;
} else {
System.out.println("Sorry, that's incorrect!");
}
System.out.println();
System.out.println("Looks like you got " + numCorrect + " / 3 correct.");
System.out.println("Thanks for playing!");
}
}
Output
[40] Modulus Animation
Goal: Create a little animation using modulus arithmetic and If statements.
/// Name: Cornelius Eanes
/// Period: 5
/// Program Name: Modulus Animation
/// File Name: ModulusAnimation.java
/// Date Finished: Oct 14, 2015
public class ModulusAnimation {
public static void main(String[] args) throws Exception {
int repeats = 5, framesPerSecond = 5, framesPerCycle = 14;
for (int i = 0; i < framesPerCycle * repeats + 1; i++) {
if (i % framesPerCycle == 0) {
System.out.print(" ..ooOoo.. \r");
} else if (i % framesPerCycle == 1) {
System.out.print(" ..ooOoo.. \r");
} else if (i % framesPerCycle == 2) {
System.out.print(" ..ooOoo.. \r");
} else if (i % framesPerCycle == 3) {
System.out.print(" ..ooOoo.. \r");
} else if (i % framesPerCycle == 4) {
System.out.print(" ..ooOoo.. \r");
} else if (i % framesPerCycle == 5) {
System.out.print(" . ..ooOoo. \r");
} else if (i % framesPerCycle == 7) {
System.out.print(" .. ..ooOoo \r");
} else if (i % framesPerCycle == 8) {
System.out.print(" o.. ..ooOo \r");
} else if (i % framesPerCycle == 9) {
System.out.print(" oo.. ..ooO \r");
} else if (i % framesPerCycle == 10) {
System.out.print(" Ooo.. ..oo \r");
} else if (i % framesPerCycle == 11) {
System.out.print(" oOoo.. ..o \r");
} else if (i % framesPerCycle == 12) {
System.out.print(" ooOoo.. .. \r");
} else if (i % framesPerCycle == 13) {
System.out.print(" .ooOoo.. . \r");
}
Thread.sleep(1000 / framesPerSecond);
}
}
Output
Of course, this is just a still image. I might replace it with a GIF.