A = fill(Vector{Int}(), (1000, 1000));
A .= copy.((Vector{Int}(),));
Or
A = [copy(Vector{Int}()) for i in 1:1000, j in 1:1000];
A = fill(Vector{Int}(), (1000, 1000));
A .= copy.((Vector{Int}(),));
Or
A = [copy(Vector{Int}()) for i in 1:1000, j in 1:1000];