how to initialize an array of std::vector?

Question

As we all know, it's normal to initialize an array of int like this:

int intAry[] = {7, 8, 9};

So, I want to know, how can initialize an array of std::vector in the same way(just in the initial list):

typedef std::vector<int> type;
type vecAry[] = {vec1, vec2, vec3};

I know it's legal to write code as fllows, now my question how to initialize vecAry in one line of code:

type vec1;
type vec2;
type vec3;
type vecAry = {vec1, vec2, vec3};

@Hitesh Vaghani, why ask my requirement? I want to implement design pattern in my code. — Triumphant
– Triumphant, Commented Jul 25, 2013 at 10:50
in your post should be type vecAry[] = {vec1, vec2, vec3}; ? — Meloun
– Meloun, Commented Jul 25, 2013 at 11:16

Mike Seymour · Accepted Answer · 2013-07-25 23:30:26Z

4

In C++11,

type vecAry[] {{},{},{}};

or if you want non-empty vectors

type vecAry[] {{1,2,3},{4,5,6},{7,8,9}};

If you're stuck in the past, you can initialise it with empty vectors:

type vecAry[] = {type(), type(), type()};

but you can't initialise it with arbitrary values without some kind of helper like those in the Boost Assignment library:

type vecAry[] = {list_of(1)(2)(3), list_of(4)(5)(6), list_of(7)(8)(9)};

answered Jul 25, 2013 at 10:50

Mike Seymour

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