лексикографическая сортировка

#include <iostream>
#include <cmath>
#include <string>

using namespace std;

void first_sort (string *arr, int n)
{
   for (int i=1; i<n; ++i)
      for (int j=0; j<n-i; j++)
        if (arr[j] > arr[j+1])
         swap (arr[j], arr[j+1]);
}

int main()
{
  cout.flush();
  int n = 0, index = 0;
  cin >> n;

 string *arr = new string[n];

  for (int i = 0; i<n; i++)
  {
    string buffer;
    cin >> buffer;
    arr[i] = buffer;
  }

first_sort(arr, n);


for (int i = 0; i<n; i++)
  cout << arr[i] << " ";

}