foo.cc: In function 'void work(int, const char&)':
foo.cc:8:30: warning: narrowing conversion of '((n % 10) + 48)' from 'int' to 'char' [-Wnarrowing]
    8 |         char sta[10]= {1,n%10+'0'};
      |                          ~~~~^~~~
foo.cc:10:21: warning: array subscript has type 'char' [-Wchar-subscripts]
   10 |                 sta[++sta[0]]=n%10+'0';
      |                     ^~~~~~~~
foo.cc:12:35: warning: array subscript has type 'char' [-Wchar-subscripts]
   12 |                 putchar(sta[sta[0]--]);
      |                             ~~~~~~^~

Found 5 testcases.
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