Main.cc: In function 'int main()':
Main.cc:5:16: error: unable to find numeric literal operator 'operator""a'
cout<<1000-4a
^
Main.cc:5:16: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes
Main.cc:4:6: warning: unused variable 'a' [-Wunused-variable]
int a=220;
^