doubt in using 2D vectors

[amscompit]

I have a written the following code.


#include<iomani p>
#include<fstrea m>
#include<vector >
#include<cctype >

using namespace std;

void PRINT(const vector< vector<string> > &M) {
for (unsigned int r=0; r<M.size(); r++) {
for (unsigned int c=0; c<M[r].size(); c++)
cout << "\t" << M[r][c]<<endl;
cout << endl;
}
}


int main()
{
unsigned int rows , cols;
rows = 1;

string line;
string token;
ifstream file;
file.open("myte xt.txt");

vector< vector<string> > v1(rows);
vector<string> v2;


while(getline(f ile,line)){
v2. push_back(line) ;}


for(unsigned int i = 0 ; i < rows ; i++){

v1[i] = v2;

}


PRINT(v1);



file.close();
system("PAUSE") ;
return 0;
}

What i want to do is read the document in a vector, then sort each line row by row. Lets say for example, i want to put line 1 in 1st row, line 2 in second row..and so on. But this code isnt doing that. Its just taking whole document and pushes into one row. How do i solve my problem?
I am just using vectors. i dont want to use algorithms or maps. JUST VECTORS.
Thanks in advance.

[weaknessforcats]

Your 2D vector is v1.

That means you have to push_back a vector<string> into v1 for each row.

So, you create a vector<string> and and push_back the strings for row 0.

Then push_back this vector into v1.

Then erase the vector<string> and re-use it to push_back the strings for row 1.

ertc...

Then you can access a particular string using v1[row][col].

[amscompit]

So, if i create a for loop, say
for(int row = 0 ; row < v1.size() ; ++row)
{
v1.push_back(ve ctor<string>()) ;
}

is tat goin to work?

[amscompit]

How will i generate a loop like tat?

[weaknessforcats]

Somethuing like this:

vector< vector<string> > v;
   vector<string> v1;
 
   string data("Hello");
   v1.push_back(data);
   string data1("world!");
   v1.push_back(data1);
   v.push_back(v1);
   v1.erase(v1.begin(), v1.end());
   string data2("from a");
   v1.push_back(data2);
   string data3("2D vector");
   v1.push_back(data3);
   v.push_back(v1);
   cout << v[0][0] << v[0][1] << v[1][0] << v[1][1] << endl;
 

[amscompit]

But thats for individual strings. What if i am reading it from file?

[weaknessforcats]

What's a file got to do with it?

Just read your file data into striong objects and push_back the string objects.

The only difference is I hard-coded "Hello" where you would have read it from the disc. And that has nothing whatsoever to do with string objects in a vector.

You might consider a new thread about how to read a disc file into a string object.