Authors:
Walter Savitch ,kenrick Mock
Chapter:
Flow Of Control
Exercise:
Programming Projects
Question:11 | ISBN:9780132830317 | Edition: 5
Question
You have three identical prizes to give away and a pool of 30 finalists. The finalists are assigned numbers from 1 to 30. Write a program to randomly select the numbers of three finalists to receive a prize. Make sure not to pick the same number twice. For example, picking finalists 3, 15, 29 would be valid but picking 3, 3, 31 would be invalid because finalist number 3 is listed twice and 31 is not a valid finalist number.
Answer
Program:
// ThreeFinalists.java
import java.util.Random;
public class ThreeFinalists
{
public static void main(String[] args)
{
Random rand = new Random();
int num, finalist1 = 0, finalist2 = 0, finalist3 = 0;
do
{
num = 1 + rand.nextInt(30);
if(finalist1 == 0)
{
finalist1 = num;
}
else if(finalist2 == 0 && finalist1 != num)
{
finalist2 = num;
}
else if(finalist3 == 0 && finalist1 != num && finalist2 != num)
{
finalist3 = num;
}
}while(finalist1 == 0 || finalist2 == 0 || finalist3 == 0);
System.out.println("Finalist #1: " + finalist1);
System.out.println("Finalist #2: " + finalist2);
System.out.println("Finalist #3: " + finalist3);
}
}
Output:
Finalist #1: 21
Finalist #2: 8
Finalist #3: 19