Compilare: user.cpp: In function ‘int act()’: user.cpp:133:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) ^ user.cpp: In function ‘int main()’: user.cpp:191:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v.size();++i) ^ user.cpp:210:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) ^ user.cpp:242:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) ^ user.cpp:248:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<sol.size();++i) g<<sol[i].F+1<<' '<<sol[i].S+1<<'\n'; ^ user.cpp: In member function ‘char InParser::read_ch()’: user.cpp:15:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^