Compilare: main.cpp:1:2: warning: #import is a deprecated GCC extension [-Wdeprecated] #import<fstream> ^~~~~~ main.cpp:2:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] main(){std::fstream c("clasic.in");std::ofstream o("clasic.out");int N,R,x;for(c>>N;c>>N;o<<R<<"\n")for(R=0;N--;R^=x)c>>x;} ^