#include <stdio.h>

int main (int argc, char **argv) {

char *a[] = { "y", NULL };

char **b = --argc ? ++argv : a;

for (;;) {

for (char **s = b; *s; s++) {

printf(*(s+1) ? "%s " : "%s", *s);

}

printf("\n");

}

return 0;

}