foo.cc:1:1: error: 'b' does not name a type
    1 | b=1;
      | ^
foo.cc:2:3: error: expected unqualified-id before 'while'
    2 |   while(b==1){
      |   ^~~~~
foo.cc:11:3: error: expected unqualified-id before 'if'
   11 |   if(b==1){
      |   ^~

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