import java.util.Scanner;

public class Grades
{
  public static void main(String[] args)
  {
    Scanner keyboard = new Scanner (System.in);
    System.out.println("Please provide the numeric value of your overall grade in a class: ");
    int n = keyboard.nextInt();
    if(n >= 90)
    {
    System.out.println("A");
    }

    if(n >= 80 && n <=89)
    {
    System.out.println("B");
    }

    if(n >= 70 && n <= 79)
    {
    System.out.println("C");
    }

    if(n >= 60 && n <= 69)
    {
    System.out.println("D");
    }

    if(n >= 0 && n <= 59)
    {
    System.out.println("F");
    }
  }
}


import java.util.Scanner;

public class IPaddress {

  public static void main(String[] args) {
    Scanner s = new Scanner(System.in);
    System.out.println("Please enter the first octet:");
    int input1 = s.nextInt();
    System.out.println("Please enter the second octet:");
    int input2 = s.nextInt();
    System.out.println("Please enter the third octet:");
    int input3 = s.nextInt();
    System.out.println("Please enter the fourth octet:");
    int input4 = s.nextInt();
    boolean valid = true;
    if (input1 < 0 || input1 > 255) {
      System.out.println("Octet 1 is incorrect");
      valid = false;
    }
    if (input2 < 0 || input2 > 255) {
      System.out.println("Octet 2 is incorrect");
      valid = false;
    }
    if (input3 < 0 || input3 > 255) {
      System.out.println("Octet 3 is incorrect");
      valid = false;
    }
    if (input4 < 0 || input4 > 255) {
      System.out.println("Octet 4 is incorrect");
      valid = false;
    }
    if (valid) {
      System.out.println("IP Address: "
          + input1 + "." + input2 + "." + input3 + "." + input4);
    }
  }
}