89 lines
1.9 KiB
Java
89 lines
1.9 KiB
Java
class BinaryVsLinear
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{
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private static int linearSearch(int key, int[] array)
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{
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int comparisons = 0;
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for (int i = 0; i < array.length; i += 1) {
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comparisons += 1;
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if (array[i] == key)
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return comparisons;
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}
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return comparisons;
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}
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private static int binarySearch(int key, int[] array)
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{
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int comparisons = 0;
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int low = 0, high = array.length - 1;
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while (low < high) {
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int mid = (low + high) / 2;
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comparisons += 1;
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if (array[mid] == key)
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return comparisons;
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comparisons += 1;
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if (array[mid] < key)
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low = mid + 1;
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else
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high = mid - 1;
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}
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return comparisons;
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}
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public static void main(String[] args)
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{
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for (int length = 1; length <= 30; length += 1)
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{
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int[] array = new int[length];
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for (int index = 0; index < length; index += 1)
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{
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array[index] = index;
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}
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double linearTotal = 0.0;
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double binaryTotal = 0.0;
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for (int element = 0; element < length; element += 1)
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{
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linearTotal += linearSearch(element, array);
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binaryTotal += binarySearch(element, array);
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}
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double linearAverage = linearTotal / length;
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double binaryAverage = binaryTotal / length;
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System.out.println(length + " " + linearAverage + " " + binaryAverage);
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}
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}
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}
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/* OUTPUT
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1 1.0 0.0
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2 1.5 1.5
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3 2.0 1.6666666666666667
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4 2.5 2.5
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5 3.0 3.0
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6 3.5 3.1666666666666665
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7 4.0 3.2857142857142856
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8 4.5 3.75
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9 5.0 4.111111111111111
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10 5.5 4.4
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11 6.0 4.636363636363637
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12 6.5 4.75
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13 7.0 4.846153846153846
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14 7.5 4.928571428571429
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15 8.0 5.0
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16 8.5 5.25
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17 9.0 5.470588235294118
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18 9.5 5.666666666666667
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19 10.0 5.842105263157895
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20 10.5 6.0
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21 11.0 6.142857142857143
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22 11.5 6.2727272727272725
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23 12.0 6.391304347826087
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24 12.5 6.458333333333333
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25 13.0 6.52
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26 13.5 6.576923076923077
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27 14.0 6.62962962962963
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28 14.5 6.678571428571429
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29 15.0 6.724137931034483
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30 15.5 6.766666666666667
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*/ |