"""
adjacent matrix <=> adjacent list
with weights
"""
from math import inf


def matrix2list(matrix):
    result = []
    N = len(matrix)
    for i in range(N):
        tmp1 = []
        for j in range(N):
            if matrix[i][j] and matrix[i][j] != inf:
                tmp1.append(((i, j), matrix[i][j]))
        result.extend(tmp1)
    return result


def list2matrix(table):
    N = 0
    # 找到结点数目
    for i in range(len(table)):
        N = max(*table[i][0], N)
    # 这里不能直接使用列表乘法
    ret = [[inf] * (N + 1) for _ in range(N + 1)]
    # 对角线置零
    for i in range(N + 1):
        ret[i][i] = 0
    # 开始赋值
    for (i, j), w in table:
        ret[i][j] = w
    return ret


matrix = [
    [0, 2, inf, inf, inf],
    [2, 0, inf, 3, 2],
    [inf, inf, 0, inf, 1],
    [inf, 3, inf, 0, 4],
    [inf, 2, 1, 4, 0]
]


tb = matrix2list(matrix)
print(tb)
for (i, j), k in tb:
    print((i, j), k, sep="\t\t")

tb1 = [((0, 1), 2), ((1, 0), 2), ((1, 3), 3), ((1, 4), 2),
       ((2, 4), 1), ((3, 1), 3), ((3, 4), 4), ((4, 1), 2),
       ((4, 2), 1), ((4, 3), 4)]

mat = list2matrix(tb1)
print(mat)
# [[0, 2, inf, inf, inf],
#  [2, 0, inf, 3, 2],
#  [inf, inf, 0, inf, 1],
#  [inf, 3, inf, 0, 4],
#  [inf, 2, 1, 4, 0]]