Main.cc: In function 'int main()': Main.cc:10:14: error: expected primary-expression before ')' token if(a%2!=-) ^ Main.cc:8:11: warning: unused variable 'b' [-Wunused-variable] int a,b,c,d; ^ Main.cc:8:13: warning: unused variable 'c' [-Wunused-variable] int a,b,c,d; ^ Main.cc:8:15: warning: unused variable 'd' [-Wunused-variable] int a,b,c,d; ^