def MST_prim(self):
        h = MinHeap()

        h.push(Element(0, 0, None))

        while not h.is_empty():
            elem_v = h.pop()

            adj_v = self.adj_list[v]
            for u, w_u_v in adj_v:
                if u not in TV and w_u_v < w_list[u]:
                    h.decrease_weight(Element(u, w_u_v, v))

    def dijkstra(self, s):
        pq = MinPriorityQueue()

        pq.push((0, s))

        while len(S) < self.vertex_num:
            d, v = pq.pop()

            adj_v = self.adjacent_set(v)
            for u, w_u_v in adj_v:
                if u not in S and distance[u] > distance[v]+w_u_v:
                    pq.push((distance[u], u))