construct a vector from brackets of integers

Question

I was wondering how to do the following efficiently. Given brackets of integers, create a stl vector accordingly?

e.g. given

[[-9],[-8,0],[-3,2,5],[6,3,0,-4],[-2,-9,-5,-8,6],[0,-5,0,-2,-1,5],[0,6,-1,-5,-8,6,-5],[-8,-5,-9,-8,-4,-3,-5,7]]

then, construct a 2d vector from it.

vector<vector <int> > vv;

EDIT:

I do not have latest compiler with c++11, so the way that directly construct like,

std::vector v({ 1, 2, 3, 4, 5 });

is not what I want.
what I currently have in mind is as follows.

int x1[1]={-9};

int x2[2]={-8, 0}; ...

std::vector v1(x1, x1 + sizeof x1 / sizeof x1[0]);

std::vector v2(x2, x2 + sizeof x2 / sizeof x2[0]); ...

vv.push_back(v1);

vv.push_back(v2); ...

But this is too tedious, and I have quite a lot of brackets.

What have you tried so far? How well did it work? What didn't work? Can you elaborate what you consider "efficiently"? — Some programmer dude, Sep 16 '13 at 08:40
Given that input when? At compile-time to add to the source? At run-time to be parsed? — Jonathan Wakely, Sep 16 '13 at 08:42
@Troy hehe ya.. He has to ensure he has a recentish compiler tho — Karthik T, Sep 16 '13 at 08:45
Do you want to *parse* such a string and turn it into a vector dynamically or do you just want to find an easy way to make that in code? — Marc Claesen, Sep 16 '13 at 08:53

score 1 · Answer 1 · answered Sep 16 '13 at 08:49

1

Did you mean:

#include <vector>

int main()
{
  std::vector<std::vector<int>> vv = {{-9},{-8,0},{-3,2,5},{6,3,0,-4},{-2,-9,-5,-8,6},{0,-5,0,-2,-1,5},{0,6,-1,-5,-8,6,-5},{-8,-5,-9,-8,-4,-3,-5,7}}; 
}

Live example (gcc / clang in C++11 mode).

answered Sep 16 '13 at 08:49

TemplateRex

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construct a vector from brackets of integers

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