46 lines
1.4 KiB
Java
46 lines
1.4 KiB
Java
// arrays/IceCream.java
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// (c)2016 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
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// Returning arrays from methods
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import java.util.*;
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import static onjava.ArrayShow.*;
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public class IceCream {
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private static SplittableRandom rand =
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new SplittableRandom(47);
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static final String[] FLAVORS = {
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"Chocolate", "Strawberry", "Vanilla Fudge Swirl",
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"Mint Chip", "Mocha Almond Fudge", "Rum Raisin",
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"Praline Cream", "Mud Pie"
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};
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public static String[] flavorSet(int n) {
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if(n > FLAVORS.length)
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throw new IllegalArgumentException("Set too big");
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String[] results = new String[n];
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boolean[] picked = new boolean[FLAVORS.length];
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for(int i = 0; i < n; i++) {
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int t;
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do
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t = rand.nextInt(FLAVORS.length);
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while(picked[t]);
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results[i] = FLAVORS[t];
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picked[t] = true;
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}
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return results;
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}
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public static void main(String[] args) {
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for(int i = 0; i < 7; i++)
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show(flavorSet(3));
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}
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}
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/* Output:
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[Praline Cream, Mint Chip, Vanilla Fudge Swirl]
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[Strawberry, Vanilla Fudge Swirl, Mud Pie]
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[Chocolate, Strawberry, Vanilla Fudge Swirl]
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[Rum Raisin, Praline Cream, Chocolate]
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[Mint Chip, Rum Raisin, Mocha Almond Fudge]
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[Mocha Almond Fudge, Mud Pie, Vanilla Fudge Swirl]
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[Mocha Almond Fudge, Mud Pie, Mint Chip]
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*/
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