foo.cc: In function 'int count_7(int)':
foo.cc:10:10: warning: variable 'c' set but not used [-Wunused-but-set-variable]
  int a,b,c;
          ^
foo.cc: In function 'int main()':
foo.cc:27:6: warning: 'e' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<e;
  ~~~~^~~

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