Compilare: user.cpp: In function ‘int main()’: user.cpp:14:24: warning: unused variable ‘x_f’ [-Wunused-variable] double a, b, x_i, y_i,x_f,y_f,m,a2,b2,c2; ^ user.cpp:14:28: warning: unused variable ‘y_f’ [-Wunused-variable] double a, b, x_i, y_i,x_f,y_f,m,a2,b2,c2; ^ user.cpp:14:32: warning: unused variable ‘m’ [-Wunused-variable] double a, b, x_i, y_i,x_f,y_f,m,a2,b2,c2; ^ user.cpp:14:34: warning: unused variable ‘a2’ [-Wunused-variable] double a, b, x_i, y_i,x_f,y_f,m,a2,b2,c2; ^ user.cpp:14:37: warning: unused variable ‘b2’ [-Wunused-variable] double a, b, x_i, y_i,x_f,y_f,m,a2,b2,c2; ^ user.cpp:14:40: warning: unused variable ‘c2’ [-Wunused-variable] double a, b, x_i, y_i,x_f,y_f,m,a2,b2,c2; ^