foo.cc: In function 'int main()':
foo.cc:6:5: warning: 'a' is used uninitialized in this function [-Wuninitialized]
  max=a;
  ~~~^~
foo.cc:7:2: warning: 'b' is used uninitialized in this function [-Wuninitialized]
  if(max<=b)
  ^~
foo.cc:11:6: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<max;
  ~~~~^~~~~

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