Compilare: user.cpp: In function ‘int main()’: user.cpp:12:11: warning: variable ‘x2’ set but not used [-Wunused-but-set-variable] double x1,x2,x3,y1,y2,y3; ^ user.cpp:12:20: warning: variable ‘y2’ set but not used [-Wunused-but-set-variable] double x1,x2,x3,y1,y2,y3; ^ user.cpp:92:11: warning: unused variable ‘nr’ [-Wunused-variable] int v[31],nr=1; ^