// C++ code to demonstrate sorting of
// 2D vector on basis of no. of columns
// in ascending order
#include<iostream>
#include<vector> // for 2D vector
#include<algorithm> // for sort()
using namespace std;
// Driver function to sort the 2D vector
// on basis of a no. of columns in
// ascending order
bool sizecom(const vector<int>& v1, const vector<int>& v2)
{
return v1.size() < v2.size();
}
int main()
{
// Initializing 2D vector "vect" with
// values
vector< vector<int> > vect{{1, 2},
{3, 4, 5},
{6}};
// Displaying the 2D vector before sorting
cout << "The Matrix before sorting is:\n";
for (int i=0; i<vect.size(); i++)
{
//loop till the size of particular
//row
for (int j=0; j<vect[i].size() ;j++)
cout << vect[i][j] << " ";
cout << endl;
}
//Use of "sort()" for sorting on
//basis of no. of columns in
//ascending order.
sort(vect.begin(), vect.end(), sizecom);
// Displaying the 2D vector after sorting
cout << "The Matrix after sorting is:\n";
for (int i=0; i<vect.size(); i++)
{
//loop till the size of particular
//row
for (int j=0; j<vect[i].size() ;j++)
cout << vect[i][j] << " ";
cout << endl;
}
return 0;
}