access an element of a vector that is inside a vector

[kasmador]

Hey,

If I have :
vector < vector<int> > temp;

And I want to access the first integer of the first vector inside temp, how would I code that up ?
Given that both the first vector and integer do exist.

temp[0][0]; does not seem to work...


Cheers,

[Albatross]

Could we see the whole code you were using, because maybe the problem is that temp[0][0] wasn't defined... what did you do to get an integer value into that position?

-Albatross

[kasmador]

So, that is the correct way of accessing that integer ?

	for (int i=0; i<temp.size(); i++) {
		for (int j=0; i<temp[i].size(); j++) {
			first[i].push_back(temp[i][temp[i].size()-j]);
		}
	}

I'm positive there is an integer to get from there. Although I can post the full code if this still does not find the culprit.

[Albatross]

Careful @Line 2. There's an i where there should be a j, no?

And Line 3... what the heck are you trying to do there?

-Albatross

[kasmador]

I have :
vector < vector<int> > temp
temp[0] = {1,2,3}
temp[1]= {4,5,6}

and
vector < vector<int> > first

What I want to do is inverse the order of the integers from the vectors in temp. Thus in the end I want to have :

first[0]={3,2,1}
first[1]={6,5,4}

To do this I thought of accessing the last integer of the first vector of temp and push_back the first vector of first.

[Albatross]

http://cplusplus.com/reference/algorithm/reverse/

-Albatross