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#include <stdio.h>
#include <time.h>
#include <stc/crand.h>
int main(void)
{
const long long N = 10000000, range = 1000000;
const uint64_t seed = (uint64_t)time(NULL);
crand_t rng = crand_init(seed);
clock_t t;
printf("Compare speed of full and unbiased ranged random numbers...\n");
long long sum = 0;
t = clock();
c_forrange (N) {
sum += (int32_t)crand_u64(&rng);
}
t = clock() - t;
printf("full range\t\t: %f secs, %lld, avg: %f\n",
(double)t/CLOCKS_PER_SEC, N, (double)(sum/N));
crand_uniform_t dist1 = crand_uniform_init(0, range);
rng = crand_init(seed);
sum = 0;
t = clock();
c_forrange (N) {
sum += crand_uniform(&rng, &dist1); // unbiased
}
t = clock() - t;
printf("unbiased 0-%lld\t: %f secs, %lld, avg: %f\n",
range, (double)t/CLOCKS_PER_SEC, N, (double)(sum/N));
sum = 0;
rng = crand_init(seed);
t = clock();
c_forrange (N) {
sum += (int32_t)crand_u64(&rng) % (range + 1); // biased
}
t = clock() - t;
printf("biased 0-%lld \t: %f secs, %lld, avg: %f\n",
range, (double)t/CLOCKS_PER_SEC, N, (double)(sum/N));
}
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