Question

Specifications:

Write a Java program called LifeRaft.java that will do all of the following:

1. Display a title
2. Ask the user to enter the following values:
   1. The type of plane(Boeing 747 or Airbus A300)
   2. The number of passengers on board the Plane
   3. The number of crew aboard the plane
   4. The maximum number of people that can be carried by one liferaft assuming all the liferafts on the plane are the same size
   5. The actual number of liferafts that are available on board the plane

3. Calculate and display the following results:
   1. The minimum number of liferafts required to carry all the people
   2. The number of people that would be rescued if the available liferafts were filled (but not beyond the number of people on board the plane) as well as the percentage that this represents of all the people on board
   3. The number of people that would drown as well as the percentage that this represents of all the people on board
   4. If nobody drowns, then also display the number of additional people that could be carried by the liferafts if they were all filled to capacity regardless of whether this number is greater than the number of people on board.

Example 1:

• If there are 240 passengers and 8 crew, and each liferaft can carry 40 people, then we need 7 liferafts. With 7 liferafts, up to 7 x 40 = 280 people can be carried. Note that 6 liferafts can only carry 240 people, which is not enough!
• If there are 6 liferafts available then only 6 x 40 = 240 people will be rescued (100 x 240 / 248 = 96.77%). This means 248 – 240 = 8 people will drown (100 x 8 / 240 = 3.33%).

Example 2:

• If there are 240 passengers and 8 crew, and each liferaft can carry 40 people, then we need 7 liferafts. With 7 liferafts up to 7 x 40 = 280 people can be rescued.
• If there are 7 liferafts available then 7 x 40 = 280 people could be rescued, but there are only 248 people so only 248 will be saved (100%) and nobody drowns (0%).
• With 7 liferafts the excess capacity would be 280 – 248 = 32 additional people.

Answer 1

LifeRaft.java:

import java.util.*;
public class LifeRaft
{
   public static void main(String[] args) {
       Scanner sc=new Scanner(System.in);
       String planeType;
       do{
           System.out.print("Enter type of plane:");
           planeType=sc.nextLine();
           if(planeType.equals("Airbus A300") || planeType.equals("Boeing 747")){ break;}
       }while(true);
       System.out.print("No. of passengers:");
       int passengers=sc.nextInt();
       System.out.print("No. of crew:");
       int crew=sc.nextInt();
       System.out.print("Maximum no. of passengers taken by single liferaft:");
       int capacity=sc.nextInt();
       System.out.print("No. of liferaft:");
       int liferaft=sc.nextInt();
       int people=passengers+crew;
       int temp=liferaft;
       int requiredLiferaft;
       if(temp*capacity<people){
           requiredLiferaft=temp;
       }
       else{
           while(temp*capacity>people)
           {
           temp-=1;
           }
           requiredLiferaft=temp+1;
       }
       System.out.println("Minimum number of liferafts required:"+requiredLiferaft);
       int rescued=requiredLiferaft*capacity>people?people:requiredLiferaft*capacity; //People rescued
       int remaining=requiredLiferaft*capacity-rescued;
       int drown=people-rescued;
       System.out.println("No. of people that can be rescued:"+rescued);
       System.out.printf("percentage of people rescued: %.2f\n",(float)rescued/(float)people*100);
       System.out.println("No. of people that can be drown:"+drown);
       System.out.printf("percentage of people drown: %.2f\n",(float)drown/(float)people*100);
       if(requiredLiferaft != liferaft){
           System.out.println("No. of people that can be rescued with remaining liferaft:"+((liferaft-requiredLiferaft)*capacity+remaining));
}
       else{
           System.out.println("No. of people that can be rescued with remaining liferaft:0");
       }
   }
}

output:

It will not accept the type of plane if it is neither "Airbus A300" nor "Boeing 747"