foo.cc: In function 'int main()':
foo.cc:23:7: warning: 'e' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if((w+e)%10==q)
     ~~^~~
foo.cc:23:7: warning: 'w' may be used uninitialized in this function [-Wmaybe-uninitialized]
foo.cc:23:2: warning: 'q' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if((w+e)%10==q)
  ^~
foo.cc:16:3: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if(y==2)
   ^~

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