/in/foo.cc: In function 'int main()':
/in/foo.cc:9:22: error: unable to find numeric literal operator 'operator""\U0000ff1b'
    9 |         int m=s%3600/60；
      |                      ^~~~
/in/foo.cc:9:22: note: use '-fext-numeric-literals' to enable more built-in suffixes
/in/foo.cc:11:31: error: 'sec' was not declared in this scope
   11 |         cout<<h<<":"<<m<<":"<<sec<<endl;
      |                               ^~~