Main.cc:14:20: warning: invalid suffix on literal; C++11 requires a space between literal and identifier [-Wliteral-suffix] cout<a+b+c<<<<" "a<<" "<<b<<" "<<c; ^ Main.cc: In function 'int main()': Main.cc:14:18: error: expected primary-expression before '<<' token cout<<a+b+c<<<<" "a<<" "<<b<<" "<<c; ^ Main.cc:14:23: error: expected ';' before 'a' cout<<a+b+c<<<<" "a<<" "<<b<<" "<<c; ^