def score(*args):
		"""Get score of core-periphery pairs.
		
		Parameters
		----------
		G : Graph object. 
		c : Dict object,  the keys and values of which are the name of node and its ID of belonging core-periphery pair.  
		
		
		Returns
		-------
		q : List. q[i] is the quality of core-periphery pair i.  
			
		"""
		self = args[0]

		if len(args) ==1:
			return self.qs_
		else:
			G = args[1]
			c = args[2]
			x = args[3]
			return self._score(G, c, x)