foo.cc: In function 'int main()':
foo.cc:13:8: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   13 |  cout<<c;
      |        ^
foo.cc:10:4: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
   10 |   b+=1;
      |   ~^~~

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