python【数据结构与算法】P3371 【模板】单源最短路径（弱化版）

import math
import cmath
import copy
import sys
import string
import heapq
import bisect
from itertools import permutations,combinations
from queue import Queue,LifoQueue,PriorityQueue
from collections import Counter,deque
from functools import cmp_to_key