foo.cc: In function ‘int main()’:
foo.cc:19:23: error: expected primary-expression before ‘<’ token
   19 |                 cout<<<1<<" "<<1<<" "<<2<<" ";
      |                       ^
foo.cc:19:25: error: invalid operands of types ‘int’ and ‘const char [2]’ to binary ‘operator<<’
   19 |                 cout<<<1<<" "<<1<<" "<<2<<" ";
      |                        ~^~~~~
      |                        |  |
      |                        |  const char [2]
      |                        int
foo.cc:25:28: error: unable to find numeric literal operator ‘operator""；’
   25 |                         i+=1；
      |                            ^~~
foo.cc:25:28: note: use ‘-fext-numeric-literals’ to enable more built-in suffixes