I would like to know, can I use insert keyword to add elements into vector
of vector
?
vector
vector<int&开发者_JS百科gt; temp1;
for this vector
, elements add within the inner for
loop. at the end of out for
loop, I need to add the elements to temp1
;
vector<vector<int> >temp1;
for (int a;a<size(),a++){//...
vector<int> temp2;
for (int b=0;b<closer_points;b++){
// some steps here...
vector<int> pt_no=mydata.Find_End_point(my_list,s1,s2);
temp2=pt_no;
}
temp1[a].insert(temp1[a].end(),temp2.begin(),temp2.end());
}
then, i tried to print temp1
, line by line as elements of temp2
are appearing in a one line.
for(int i=0;i<temp1.size();i++){
for(int j=0;j<temp1[i].size();j++){
cout<<" t2 "<<temp1[i][j];
}
cout<<endl;
}
but, this doesnt work. can anyone rectify this, plz...
Question:
temp1[a].insert(temp1[a].end(),temp2.begin(),temp2.end());
Reinstated prior answer:
To append a range of values to an existing vector:
std::copy(temp2.begin(),temp2.end(), std::back_inserter(temp1));
To append the range as a new vector to an existing vector_of_vectors:
vector<vector<int> > vecvec;
vector<int> toappend;
// some steps :)
vecvec.push_back(toappend);
// or
vecvec.push_back(vector<int>(toappend.begin(), toappend.end());
include <iterator>
and <algorithm>
if you haven't got them already
Update
if i say like this; i have set of points. i want to group these points into vectors and then to put those into another vector at the end. so, i gues my final output is vector of vector. for example, final result should look like ((1,3),(4,6,9,8,21),(5,7,12),..).
Ok, here goes:
// (
std::vector<std::vector<int> > vecvec;
// (1,3)
{
std::vector<int> vec;
vec.push_back(1);
vec.push_back(3);
vecvec.push_back(vec);
}
// (4,6,9,8,21)
{
std::vector<int> vec;
vec.push_back(4);
vec.push_back(6);
vec.push_back(9);
vec.push_back(8);
vec.push_back(21);
vecvec.push_back(vec);
}
// (5,7,12)
{
std::vector<int> vec;
vec.push_back(5);
vec.push_back(7);
vec.push_back(12);
vecvec.push_back(vec);
}
// )
// ....
... // (use vecvec)
You need to use temp1.push_back(temp2);
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