Boolean Notebook
ifs
- if: If the condition in the if statement is true, then the code is executed under it is executed.
- if-else: If the condition in the if statement is true, then that code under that is executed. Otherwise (if false), then the code under else is executed.
- if-elseif-else: There are 2 conditions to be met in this, with the first if's code being executed if that is true. The elseif's code will be executed if the statement for that is true. If it's false for both if and ifelse statements, then the else's code will be executed.
import java.util.Scanner;
Scanner input;
System.out.print("What color are apples?: ");
input = new Scanner(System.in);
String answer = input.nextLine();
answer = answer.toLowerCase();
System.out.println(answer);
if ((answer == "yellow") || (answer == "red") || (answer == "green")){ // will print correct if the user answers yellow, red, or green
System.out.print("You are correct");
}
else {// if the user inputs anything other than yellow, red, green, then it outputs this
System.out.print("What kind of apples are have you been looking at?");
}
System.out.println(" ");
System.out.print("On a scale of 1-10, how do you rate apples?: ");
input = new Scanner(System.in);
Double answer1 = input.nextDouble();
System.out.println(answer1);
if ((answer1 < 5) && (answer1 > 0)) { // if the user inputs a number between 1 and 4, then it prints this
System.out.print("What is wrong with you.");
}
else if ((answer1 < 8) && (answer1 >= 5)) { //if the user inputs a number between 5 and 7 it inputs this
System.out.print("That makes sense.");
}
else if ((answer1 <= 10) && (answer1 >= 8)) { // if the user inputs a number between 8 and 10 it inputs this
System.out.print("Very correct!");
}
else { // if the user doesn't input a number from 1 to 10 it inputs this
System.out.print("Your choice has to be a number between 1 and 10.");
}
import java.util.Scanner;
public class GradeCalculator {
public static void main(String args[]) {
Scanner input = new Scanner(System.in);
System.out.println("Seperate category?: ")
boolean category = input.nextBoolean();
if (category == true) {
System.out.println("current grade?: ")
double a = input.nextDouble();
System.out.println("% final: ")
double perc1 = input.nextDouble();
System.out.println("desired grade: ")
double b input.nextDouble();
double cgrade = a/100 * (100-perc1)/100;
double bgrade = b/100-cgrade;
double perc2 = bgrade/perc1;
System.out.println("needed grade: " + perc2);
}
}
}
import java.util.Scanner;
System.out.print("How old are you?: ");
Scanner num = new Scanner(System.in);
int answer = Integer.parseInt(num.nextLine());; // scanner input
System.out.println(answer); // to do age ranges, each case number had to be defined by a range in switch
switch ((0 <= answer && answer <=1) ? 0 : // "?" is if and ":" is else, so in this case if the number inputted was between 0 and 1, then it would be set as case 0, if not then it would go on to the other cases
(2 <= answer && answer <=4) ? 1 :
(5 <= answer && answer <=12) ? 2 :
(13 <= answer && answer <=19) ? 3 :
(20 <= answer && answer <=39) ? 4 :
(40 <= answer && answer <=59) ? 5 :
(60 <= answer && answer <=130) ? 6 : 7) {
case 0:
System.out.println("You're a baby."); // if between age 0 and 1, then it prints you're a baby
break;
case 1:
System.out.println("You're a toddler.");
break;
case 2:
System.out.println("You're a child.");
break;
case 3:
System.out.println("You're a teen.");
break;
case 4:
System.out.println("You're a adult.");
break;
case 5:
System.out.println("You're a middle-aged adult.");
break;
case 6:
System.out.println("You're old.");
break;
case 7:
System.out.println("How? I think you made a mistake."); //if not in the range of any of the previous cases
break;
default:
System.out.println("Try again."); //if user input bypasses all cases
break;
}
import java.util.Scanner;
public class GradeCalculator {
public static void main(String args[]) {
Scanner input = new Scanner(System.in);
System.out.println("Seperate category?: ")
boolean category = input.nextBoolean();
if (category == true) {
System.out.println("current grade?: ")
double a = input.nextDouble();
System.out.println("% final: ")
double perc1 = input.nextDouble();
System.out.println("desired grade: ")
double b input.nextDouble();
double cgrade = a/100 * (100-perc1)/100;
double bgrade = b/100-cgrade;
double perc2 = bgrade/perc1;
System.out.println("needed grade: " + perc2);
}
}
}
import java.util.Scanner;
public class GradeCalculator {
public static void main(String args[]) {
Scanner input = new Scanner(System.in);
System.out.println("Seperate category?: ");
boolean category = input.nextBoolean();
if (category == true) {
System.out.println("current grade?: ");
double a = input.nextDouble();
System.out.println("% final: ");
double perc1 = input.nextDouble();
System.out.println("desired grade: ");
double b = input.nextDouble();
double cgrade = a/100 * (100-perc1)/100;
double bgrade = b/100-cgrade;
double perc2 = bgrade/perc1;
System.out.println("needed grade: " + perc2*10000 + "%");
}
else {
System.out.println("current grade?: ");
double a = input.nextDouble();
System.out.println("desired grade: ");
double b = input.nextDouble();
System.out.println("test category %: ");
double c = input.nextDouble();
System.out.println("points in test category: ");
double d = input.nextDouble();
System.out.println("points in the final: ");
double e = input.nextDouble();
a = a/100;
b = b/100;
double total = (e/(d+e))*c; //final is this percent of the total grade
double needed = (e*(b-a))/total;
System.out.println("points needed: " + needed * 10000);
}
}
}
GradeCalculator.main(null);
Scanner input = new Scanner(System.in);
/*/
System.out.println("current grade?: ");
double a = input.nextDouble();
System.out.println("desired grade: ");
double b = input.nextDouble();
System.out.println("test category %: ");
double c = input.nextDouble();
System.out.println("current grade in test category: ");
double curr = input.nextDouble();
System.out.println("points in test category: ");
double d = input.nextDouble();
System.out.println("points in the final: ");
double e = input.nextDouble();
/*/
double a = 89;
System.out.println("desired grade: ");
double b = 90;
System.out.println("test category %: ");
double c = 80;
System.out.println("current grade in test category: ");
double curr = 90;
System.out.println("points in test category: ");
double d = 100;
System.out.println("points in the final: ");
double e = 100;
double other = a - (c * curr/100); //other category percent
System.out.println(other);
double needed = b - other;
System.out.println(needed);
double rneeded = needed/c; //needed in test category
System.out.println(rneeded);
// double current = ((fin + d)/(d + e))*100 = rneeded
double fin = ((rneeded)*(d+e))/100-d/100;
System.out.print(fin);