foo.cc: In function 'int main()':
foo.cc:34:15: warning: 'fj' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int tot=0,fi,fj;
               ^~
foo.cc:34:12: warning: 'fi' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int tot=0,fi,fj;
            ^~

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