from heapq import heappush, heappop
from sys import stdin
input = stdin.readline

inf = 1 << 60

def main():
    n, m = map(int, input().split())
    edges = [[] for _ in range(n+m)]
    for i in range(n, n+m):
        k, c, *s = map(int, input().split())
        for j in s:
            edges[j-1].append((c, i))
            edges[i].append(j-1)
    
    # Dijkstra
    heap = []
    heappush(heap, (0, 0, 0))
    costs = [(inf,inf)] * (n+m)
    while heap:
        cost, rem, i = heappop(heap)
        if costs[i] < (cost,rem):
            continue
        if i < n:
            for c, j in edges[i]:
                new_cost = (cost + c + (i+1)//2, i+1 & 1)
                if new_cost < costs[j]:
                    costs[j] = new_cost
                    heappush(heap, (new_cost[0],new_cost[1],j))
        else:
            for j in edges[i]:
                new_cost = (cost + (j+rem+2)//2, 0)
                if new_cost < costs[j]:
                    costs[j] = new_cost
                    heappush(heap, (new_cost[0],new_cost[1],j))
    
    if costs[n-1] == (inf, inf):
        print(-1)
    else:
        print(costs[n-1][0])

main()