Compilare: user.cpp: In function ‘void write()’: user.cpp:25:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<Q.size();i++) fout<<setprecision(7)<<fixed<<Q[i]<<"\n"; ^ user.cpp: In function ‘int main()’: user.cpp:29:11: warning: unused variable ‘m’ [-Wunused-variable] int n,m,i,j; ^ user.cpp:29:15: warning: unused variable ‘j’ [-Wunused-variable] int n,m,i,j; ^ user.cpp:30:12: warning: unused variable ‘sum’ [-Wunused-variable] double sum,l; ^