/in/foo.cc: In function 'void SetUnion(std::vector<int>&, std::vector<int>&)':
/in/foo.cc:21:6: error: 'i' was not declared in this scope
  for(i=0; i<size2&&v2[i]!=0; i++)
      ^
/in/foo.cc:27:6: error: 'i' was not declared in this scope
  for(i=0; i<size1&&v1[i]!=0; i++)
      ^
/in/foo.cc:33:6: error: 'i' was not declared in this scope
  for(i=0; i<size1&&v1[i]!=0; i++)
      ^
/in/foo.cc:35:6: error: 'i' was not declared in this scope
  for(i=0; i<size2&&v2[i]!=0; i++)
      ^