Created
October 31, 2012 07:24
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#include <algorithm> | |
#include <ctime> | |
#include <iostream> | |
int main() | |
{ | |
// Generate data | |
const unsigned arraySize = 32768; | |
int data[arraySize]; | |
for (unsigned c = 0; c < arraySize; ++c) | |
data[c] = std::rand() % 256; | |
// !!! With this, the next loop runs faster | |
std::sort(data, data + arraySize); | |
// Test | |
clock_t start = clock(); | |
long long sum = 0; | |
for (unsigned i = 0; i < 100000; ++i) | |
{ | |
// Primary loop | |
for (unsigned c = 0; c < arraySize; ++c) | |
{ | |
if (data[c] >= 128) | |
sum += data[c]; | |
} | |
} | |
double elapsedTime = static_cast<double>(clock() - start) / CLOCKS_PER_SEC; | |
std::cout << elapsedTime << std::endl; | |
std::cout << "sum = " << sum << std::endl; | |
} |
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