foo.cc: In function 'int main()':
foo.cc:8:11: warning: left operand of comma operator has no effect [-Wunused-value]
    8 |  for(f=0;f>=e,f++)
      |          ~^~~
foo.cc:8:18: error: expected ';' before ')' token
    8 |  for(f=0;f>=e,f++)
      |                  ^
      |                  ;

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