output_description: For each vertex, print its ID and the distance separated by a space character
  in a line respectively. Print in order of vertex IDs.
input_description: In the first line, an integer $n$ denoting the number of vertices in $G$ is
  given. In the following $n$ lines, adjacency lists for each vertex $u$ are
  respectively given in the following format:
  
  $u$ $k$ $v_1$ $c_1$ $v_2$ $c_2$ ... $v_k$ $c_k$
  
  Vertices in $G$ are named with IDs $0, 1, ..., n-1$. $u$ is ID of the target
  vertex and $k$ denotes its degree. $v_i (i = 1, 2, ... k)$ denote IDs of
  vertices adjacent to $u$ and $c_i$ denotes the weight of a directed edge
  connecting $u$ and $v_i$ (from $u$ to $v_i$).
attempt: # Graph II - Single Source Shortest Path II
  def dijkstra(length, adj_list):
      INFTY = float("inf")
      d = [INFTY for _ in range(length)]
      d[0] = 0
      Q = [i for i in range(length)]
      while Q:
          idx = INFTY
          minv = INFTY
          for q in Q:
              if d[q] < minv:
                  idx, minv = q, d[q]
          u = Q.pop(Q.index(idx))
          for v in adj_list[u]:
              if d[v[0]] > d[u] + v[1]:
                  d[v[0]] = d[u] + v[1]
      return d
  
  
  n = int(input())
  adj_list = [set() for _ in range(n)]
  for _ in range(n):
      ss = list(map(int, input().split()))
      u, k = ss[0], ss[1]
      for i in range(k):
          vi, ci = ss[2 * i + 2], ss[2 * i + 3]
          adj_list[u].add((vi, ci))
  d = dijkstra(n, adj_list)
  for i, v in enumerate(d):
      print(i, v)
  
problem_description: Single Source Shortest Path II
  
  For a given weighted graph $G = (V, E)$, find the shortest path from a source
  to each vertex. For each vertex $u$, print the total weight of edges on the
  shortest path from vertex $0$ to $u$.
samples: [{"input": "5\n    0 3 2 3 3 1 1 2\n    1 2 0 2 3 4\n    2 3 0 3 3 1 4 1\n    3 4 2 1 0 1 1 4 4 3\n    4 2 2 1 3 3", "output": "0 0\n    1 2\n    2 2\n    3 1\n    4 3"}]