Compilare: user.cpp: In function ‘int main()’: user.cpp:16:63: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(!stiva.empty() && stiva.top()<x && stiva.size()+n-i>=m) ^ user.cpp:18:70: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(!stiva.empty() && stiva.top()<x && stiva.size()+n-i>=m) ^ user.cpp:25:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(stiva.empty() || stiva.size()<m) ^ user.cpp:7:34: 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:8:36: 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:10:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d ",&n,&m); ^ user.cpp:14:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c ",&x); ^