Compilare: user.cpp: In function ‘int main()’: user.cpp:20:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(!s.empty() && s.size()+n-1-i >= m && tr[i] > s.top()) ^ user.cpp:13:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trompeta.in", "r", stdin); ^ user.cpp:14:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trompeta.out", "w", stdout); ^ user.cpp:16:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n %s", &n, &m, tr); ^