foo.cc: In function 'int main()':
foo.cc:27:32: warning: unknown conversion type character '\x0a' in format [-Wformat=]
   27 |                 printf("%.2lf\%\n", sum);
      |                                ^~
foo.cc:31:24: warning: unknown conversion type character '\x0a' in format [-Wformat=]
   31 |         printf("%.2lf\%\n", sum);
      |                        ^~

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