foo.cc: In function 'int main()':
foo.cc:6:13: warning: 'b' is used uninitialized in this function [-Wuninitialized]
  if(100*a+10*b+c==n);
           ~~^~
foo.cc:7:11: warning: 'c' is used uninitialized in this function [-Wuninitialized]
  cout<<100*c+10*b+a<<endl;
        ~~~^~
foo.cc:7:19: warning: 'a' is used uninitialized in this function [-Wuninitialized]
  cout<<100*c+10*b+a<<endl;
                   ^

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