Compilare: user.cpp: In function ‘int main()’: user.cpp:67:15: warning: unused variable ‘b’ [-Wunused-variable] int i, a, b, c, ans, st, dr, m; ^ user.cpp:67:18: warning: unused variable ‘c’ [-Wunused-variable] int i, a, b, c, ans, st, dr, m; ^ user.cpp:71:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("arborest.in", "r", stdin); ^ user.cpp:72:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("arborest.out", "w", stdout); ^ user.cpp:74:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &n, &k); ^ user.cpp:76:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &a); ^