foo.cc: In function 'int main()':
foo.cc:75:3: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
  c--;
  ~^~
foo.cc:76:11: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<a<<" "<<c;
           ^~~

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