Math Functions

An organization wants to take a trip. We need enough busses to fit everyone. (We can't tell a few people that they can't go.)

Notice that the ceil function will give us the correct number of busses. However, if we divide 30/25 we will get just one. To find the number of busses we need the ceiling (Math.ceil) function. However, ceil requires a double as an argument. Multiplying an int by 1.0 converts it to double. We could also use Math.ceil((double)numPeople/numSeats) to cast to double.

How many people are going:20
How many seats are there on a bus:16
You will need 2 busses.

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//How many busses are needed?
package busses;
import java.util.*;
public class Busses {
	public static void main(String[] args) {
		Scanner keyboard=new Scanner(System.in); //do just once
		int numPeople, numSeats, numBusses;  
		System.out.print("How many people are going:");
		numPeople=keyboard.nextInt();
		System.out.print("How many seats are there on a bus:");
		numSeats=keyboard.nextInt();
		int numberBusses=(int)(Math.ceil(1.0*numPeople/numSeats));
		System.out.println("You will need " + numberBusses + " busses."); 
	}//main
}//class
CODE

Notice that we have to cast to int to print 2 busses instead of 2.0 busses.

NEXT: Boolean Expressions