請問python list問題
>>> # case 1
>>> m = [[0,0], [1,1]]>>> n = m[:]>>> n += [[2, 2]]>>> n
[[0, 0], [1, 1], [2, 2]]>>> m
[[0,0], [1,1]]
>>> #case2
>>> u = [[0, 0], [1, 1]]>>> v = u[:]>>> u is v
False
>>> v[0] += [2]>>> v
[[0, 0, 2], [1, 1]]>>> u
[[0, 0, 2], [1, 1]]>>> v is u
False
請問一下,怎麼會這樣啊?
為什麼m跟n不會一起變
而v is not u但v跟u卻會一起變?