foo.cpp: In function 'int main()':
foo.cpp:42:2: error: expected primary-expression before '__int128'
  __int128 tmp=a+b;
  ^
foo.cpp:42:2: error: expected ';' before '__int128'
foo.cpp:43:12: error: 'tmp' was not declared in this scope
  cout<<(ll)tmp<<"\n";
            ^