add-city newyork
add-city boston
add-city newyork
add-link boston newyork
add-link boston newark
add-link newyork boston
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add-city newark
add-link newark newyork
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add-city providence
add-link providence boston
add-city albany
add-city philadelphia
add-link philadelphia newark
add-city baltimore
add-link philadelphia baltimore
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add-link newyork albany
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remove-city newyork
remove-link albany newyork
add-city newyork
add-city washington
add-link newyork providence
add-link newyork newark
add-link newyork baltimore
add-link baltimore washington
add-city pittsburgh
add-city cleveland
add-city buffalo
add-city bloomington
add-city chicago
add-link pittsburgh cleveland
add-link cleveland buffalo
add-link cleveland bloomington
add-link bloomington chicago
add-city harrisburg
add-link philadelphia harrisburg
add-link philadelphia pittsburgh
add-link harrisburg pittsburgh
add-link boston newyork
remove-link philadelphia pittsburgh
remove-link philadelphia pittsburgh
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