Compilare: main.cpp: In function 'int main()': main.cpp:35:15: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] pi[n + 1] = NULL; ^~~~ main.cpp:27:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ciurulet.in", "r", stdin); ^ main.cpp:28:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ciurulet.out", "w", stdout); ^ main.cpp:30:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &n); ^ main.cpp:31:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s", pf + 2); ^