foo.cc: In function 'int main()':
foo.cc:36:19: warning: 'd' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<n<<"="<<d<<"+"<<c;
                   ^~~
foo.cc:36:22: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<n<<"="<<d<<"+"<<c;
  ~~~~~~~~~~~~~~~~~~~~^~~

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