Notes

// 01. Convert Meters to Kilometers

import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int numbers = Integer.parseInt(scanner.nextLine());

System.out.printf(" %.2f", (double) numbers / 1000);
}
}

// 02. Pounds to Dollars

import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
double pounds = Double.parseDouble(scanner.nextLine());

double dollars = pounds * 1.36;

System.out.printf("%.3f", dollars);
}
}

// 03. Exact Sum of Real Numbers

import java.math.BigDecimal;
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int n = Integer.parseInt(scanner.nextLine());

BigDecimal sum = new BigDecimal(0);

for (int i = 0; i < n; i++) {
BigDecimal number = new BigDecimal(scanner.nextLine());
sum = sum.add(number);
}
System.out.println(sum);
}
}

// 04. City Info

import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
String city = scanner.nextLine();
String population = scanner.nextLine();
String area = scanner.nextLine();

System.out.printf("City of %s has population of %s and area %s square km.", city, population, area);
}
}

// 05. Concat Names

import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
String firstName = scanner.nextLine();
String secondName = scanner.nextLine();
String symbol = scanner.nextLine();

System.out.printf("%s%s%s", firstName, symbol, secondName);
}
}

// 06 06. Chars to String
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
Character n1 = scanner.nextLine().charAt(0);
Character n2 = scanner.nextLine().charAt(0);
Character n3 = scanner.nextLine().charAt(0);

System.out.printf("%c%c%c", n1, n2, n3);
}
}

// 07. Reversed Chars
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
Character n1 = scanner.nextLine().charAt(0);
Character n2 = scanner.nextLine().charAt(0);
Character n3 = scanner.nextLine().charAt(0);

System.out.printf("%c %c %c", n3, n2, n1);

}
}

// 08. Lower or Upper
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
Character letter = scanner.nextLine().charAt(0);

if (letter == Character.toUpperCase(letter)) {
System.out.println("upper-case");
} else if (letter == Character.toLowerCase(letter)) {
System.out.println("lower-case");
}
}
}

// 09. Centuries to Minutes
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int centuries = Integer.parseInt(scanner.nextLine());

double years = centuries * 100;
double days = years * 365.2422;
double hours = days * 24;
double minutes = hours * 60;

System.out.printf("%d centuries = %.0f years = %.0f days " +
"= %.0f hours = %.0f minutes", centuries, years, days,
hours, minutes);
}
}

// 10. Special Numbers
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int n = Integer.parseInt(scanner.nextLine());

for (int i = 1; i <= n; i++) {
int sumOfDigits = 0;
int number = i;
while (number > 0) {
sumOfDigits += number % 10;
number /= 10;
}
if (sumOfDigits == 5 || sumOfDigits == 7 || sumOfDigits == 11) {
System.out.println(i + " -> True");
} else {
System.out.println(i + " -> False");
}
}
}
}

// 11. Refactor Volume of Pyramid
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
double dul, sh, V = 0;
System.out.print("Length: ");
dul = Double.parseDouble(scanner.nextLine());
System.out.print("Width: ");
sh = Double.parseDouble(scanner.nextLine());
System.out.print("Height: ");
V = Double.parseDouble(scanner.nextLine());
V = (dul * sh * V) / 3;
System.out.printf("Pyramid Volume: %.2f", V);

}
}

// 12. Refactor Special Numbers
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
int num = Integer.parseInt(scan.nextLine());
for (int i = 1; i <= num; i++) {
int sum = 0;
int actualNum = i;
while (i > 0) {
sum += i % 10;
i = i / 10;
}
boolean trueFalse = (sum == 5) || (sum == 7) || (sum == 11);
String tF;
if (trueFalse) {
tF = "True";
} else {
tF = "False";
}
System.out.printf("%d -> %s%n", actualNum, tF);
i = actualNum;
}
}
}