G = (["A","B","C","D","E","F","G"],
     [("A","B",1),("A","D",2),("A","C",3),
      ("B","D",5),("B","E",1),("C","D",4),
      ("C","F",1),("D","E",1),("D","F",1),
      ("D","G",2),("E","G",3),("F","G",4)])

IND = {"A":0,
       "B":1,
       "C":2,
       "D":3,
       "E":4,
       "F":5,
       "G":6}

def select_min(t1, t2):
    mini = IND[t2[0]]
    for s in t2[1:]:
        if t1[mini] > t1[IND[s]]:
            mini = IND[s]
    return mini

def dijkstra(g, s):
    res = [float('inf') for _ in g[0]]
    res[IND[s]] = 0
    a_faire = [e for e in g[0]]
    while a_faire != []:
        ind_courrant = select_min(res, a_faire)
        sommet_courrant = g[0][ind_courrant]
        a_faire.remove(sommet_courrant)
        cout_courrant = res[ind_courrant]
        for l in g[1]:
            if l[0]==sommet_courrant:
                cout_tmp=l[2]+cout_courrant
                if res[IND[l[1]]]>=cout_tmp:
                    res[IND[l[1]]] = cout_tmp
    return res
            
G2 = (["A","B","C","D","E"],
      [("A","B",4),("A","C",3),("A","D",2),
       ("B","E",1),("C","D",1),("C","E",1),("D","E",1)])