def insertDomain(self, domain, indegree=0, outdegree=0):
		'''增加一个域名'''
		cur = self.conn.cursor()
		cur.execute("INSERT INTO Domains VALUES (NULL,?,?,?)", (domain, indegree, outdegree))
		# 写入到文件中
		self.conn.commit()
def inc_c(self, ind):
        r, c = self.row_col(ind)
        c += 1
        if c == self.nc:
            c = 0
        if r == (self.nr - 1) and c == (self.nc - 1):
            c = 0
        return self.indx(r, c)