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#include <sys/time.h>
#include <stdio.h>
// this should be found in include under
// the massivethreads installation directory
// (<prefix>/include)
#include <mtbb/task_group.h>
double cur_time() {
struct timeval tp[1];
gettimeofday(tp, NULL);
return tp->tv_sec + 1.0E-6 * tp->tv_usec;
}
int fib(int n) {
if (n < 2) return n;
else {
mtbb::task_group tg; int x, y;
tg.run([=,&x] { x = fib(n - 1); });
y = fib(n - 2);
tg.wait();
return x + y;
}
}
int main(int argc, char ** argv) {
int n = (argc > 1 ? atoi(argv[1]) : 35);
while (1) {
double t0 = cur_time();
int x = fib(n);
double t1 = cur_time();
printf("fib(%d) = %d in %.3f sec\n", n, x, t1 - t0);
}
}
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