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Question o Give all possible outputs of the following program. \( \begin{aligned} 1 & \\ 2 & \text { \#include } \\ 3 & \text { \#include } \\ 4 & \text { int i= 0; } \\ 5 & \text { void *do_stuff(void *arg) }\{ \\ 6 & \text { i++; } \\ 7 & \text { return NULL; } \\ 8 & \text { \} } \\ 9 & \text { int main() }\{ \\ 10 & \text { pthread_t tid1, tid2; } \\ 11 & \text { pthread_create(\&tid1, NULL, do_stuff, NULL); } \\ 12 & \text { pthread_create(\&tid2, NULL, do_stuff, NULL); } \\ 13 & \text { pthread_join(tid1, NULL); } \\ 14 & \text { pthread_join(tid2, NULL); } \\ 15 & \text { printf("8d } \backslash n ", i) ; \\ 16 & \text { return 0; } \\ 17 & \text { \} }\end{aligned} \)