Compilare: user.cpp: In function ‘int main()’: user.cpp:48:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("costsq.in", "r", stdin); ^ user.cpp:49:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("costsq.out", "w", stdout); ^ user.cpp:51:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ user.cpp:53:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &w[i], &l[i], &r[i]); ^ user.cpp: In function ‘void add_pos(int)’: user.cpp:43:25: warning: ‘aux’ may be used uninitialized in this function [-Wmaybe-uninitialized] best_from[pos] = aux; ^