Compilare: user.cpp: In function ‘int main()’: user.cpp:79:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < v.size() ; i++) ~~^~~~~~~~~~ user.cpp:106:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < drum.size() ; i++) ~~^~~~~~~~~~~~~ user.cpp:65:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("alpin.in","r",stdin); ^ user.cpp:66:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("alpin.out","w",stdout); ^ user.cpp:67:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:72:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&p); ^ user.cpp:104:21: warning: ‘posy’ may be used uninitialized in this function [-Wmaybe-uninitialized] recon(posx,posy); ^ user.cpp:104:21: warning: ‘posx’ may be used uninitialized in this function [-Wmaybe-uninitialized]