Build the graph add ( adj , x , y ) means x wins over y
add ( adj , 0 , 1 ) NEW_LINE add ( adj , 0 , 2 ) NEW_LINE add ( adj , 0 , 3 ) NEW_LINE add ( adj , 1 , 5 ) NEW_LINE add ( adj , 2 , 5 ) NEW_LINE add ( adj , 3 , 4 ) NEW_LINE add ( adj , 4 , 5 ) NEW_LINE add ( adj , 6 , 0 ) NEW_LINE