Main.cc: In function ‘int main()’: Main.cc:5:11: warning: right operand of comma operator has no effect [-Wunused-value] cin>>a,b,c,d; ^ Main.cc:5:13: warning: right operand of comma operator has no effect [-Wunused-value] cin>>a,b,c,d; ^ Main.cc:5:14: warning: right operand of comma operator has no effect [-Wunused-value] cin>>a,b,c,d; ^ Main.cc:6:4: error: ‘sgit’ was not declared in this scope m=sgit((a-b)*(a-b)+(c-d)*(c-d)); ^~~~ Main.cc:6:4: note: suggested alternative: ‘sig_t’ m=sgit((a-b)*(a-b)+(c-d)*(c-d)); ^~~~ sig_t