Main.cc: In function ‘void slv()’: Main.cc:14:5: error: ‘n’ was not declared in this scope n=read();up(i,1,n)a[i]=read(); ^ Main.cc:14:7: error: ‘read’ was not declared in this scope n=read();up(i,1,n)a[i]=read(); ^~~~ Main.cc:14:7: note: suggested alternative: ‘fread’ n=read();up(i,1,n)a[i]=read(); ^~~~ fread