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// https://quuxplusone.github.io/blog/2019/03/06/pythagorean-triples/
#include <stc/algo/coroutine.h>
#include <stdio.h>
void triples_vanilla(int n) {
for (int i = 1, z = 1;; ++z) {
for (int x = 1; x < z; ++x) {
for (int y = x; y < z; ++y) {
if (x*x + y*y == z*z) {
printf("{%d, %d, %d},\n", x, y, z);
if (++i > n) goto done;
}
}
}
}
done:;
}
struct triples {
int n;
int x, y, z;
int cco_state;
};
bool triples_coro(struct triples* t) {
cco_begin(t);
for (t->z = 1;; ++t->z) {
for (t->x = 1; t->x < t->z; ++t->x) {
for (t->y = t->x; t->y < t->z; ++t->y) {
if (t->x*t->x + t->y*t->y == t->z*t->z) {
if (t->n-- == 0) cco_return;
cco_yield(true);
}
}
}
}
cco_final:
cco_end(false);
}
int main()
{
puts("Vanilla triples:");
triples_vanilla(6);
puts("\nCoroutine triples:");
struct triples t = {6};
while (triples_coro(&t))
printf("{%d, %d, %d},\n", t.x, t.y, t.z);
}
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