Created
October 31, 2012 07:25
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import java.util.Arrays; | |
import java.util.Random; | |
public class Main | |
{ | |
public static void main(String[] args) | |
{ | |
// Generate data | |
int arraySize = 32768; | |
int data[] = new int[arraySize]; | |
Random rnd = new Random(0); | |
for (int c = 0; c < arraySize; ++c) | |
data[c] = rnd.nextInt() % 256; | |
// !!! With this, the next loop runs faster | |
Arrays.sort(data); | |
// Test | |
long start = System.nanoTime(); | |
long sum = 0; | |
for (int i = 0; i < 100000; ++i) | |
{ | |
// Primary loop | |
for (int c = 0; c < arraySize; ++c) | |
{ | |
if (data[c] >= 128) | |
sum += data[c]; | |
} | |
} | |
System.out.println((System.nanoTime() - start) / 1000000000.0); | |
System.out.println("sum = " + sum); | |
} | |
} |
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