deyou
47 lines
1.2 KiB
Java
47 lines
1.2 KiB
Java
import java.util.*;
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/**
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* This program demonstrates array manipulation.
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* @version 1.20 2004-02-10
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* @author Cay Horstmann
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*/
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public class LotteryDrawing
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{
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public static void main(String[] args)
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{
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Scanner in = new Scanner(System.in);
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System.out.print("How many numbers do you need to draw? ");
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int k = in.nextInt();
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System.out.print("What is the highest number you can draw? ");
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int n = in.nextInt();
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// fill an array with numbers 1 2 3 . . . n
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int[] numbers = new int[n];
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for (int i = 0; i < numbers.length; i++)
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numbers[i] = i + 1;
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// draw k numbers and put them into a second array
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int[] result = new int[k];
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for (int i = 0; i < result.length; i++)
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{
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// make a random index between 0 and n - 1
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int r = (int) (Math.random() * n);
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// pick the element at the random location
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result[i] = numbers[r];
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// move the last element into the random location
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numbers[r] = numbers[n - 1];
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n--;
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}
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// print the sorted array
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Arrays.sort(result);
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System.out.println("Bet the following combination. It'll make you rich!");
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for (int r : result)
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System.out.println(r);
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}
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}
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