def read_file(name):
        f = open(name,'r')
        result = []
        for line in f:
            result.append(IO.feed_line(line))
        return result

    def feed_line(line):
        result = []
        for x in line:
            if x!=' ' and x!='\n':
                if ord(x)>=ord('0') and ord(x)<=ord('9'): # integer
                    result.append(int(x))
                else:   #ascci to integer>=10
                    IO.hashmap[ord(x)-55]=x
                    result.append(ord(x)-55)
        return result

    def print_solution(node_list):
        if node_list is not None:
            path=node_list.path()
            path.reverse()
            for n in path:
                for line in n.state.array:
                    l = ""
                    for val in line:
                        if val>9:
                            l += IO.hashmap[val]
                        else:
                            l += str(val)
                        l += " "
                    print(l)
                print("")
        else:
            print("No solution")