foo.cc: In function 'int main()':
foo.cc:28:6: error: redeclaration of 'int n'
  int n,i;
      ^
foo.cc:6:5: note: 'int n' previously declared here
 int n,i;
     ^
foo.cc:28:8: error: redeclaration of 'int i'
  int n,i;
        ^
foo.cc:6:7: note: 'int i' previously declared here
 int n,i;
       ^

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