поиск среди слов

#include <iostream>
#include <string>
#include <stdio.h>

using namespace std;

int poisk (string *arr, string znach, int left, int right)
{
 int i = 0;
while (left < right)
{
  i = (left + right) / 2;
  if (arr[i] < znach)
    left = i+1;
  else right = i;
}

if (arr[right] == znach)
return right+1;
return -1;
}

int main()
{
  int n = 0, m = 0;
  scanf("%d", &n);

  string buffer;

  string *arr = new string[n];

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

scanf("%d", &m);

for (int i = 0; i < m; i++)
{
  cin >> buffer;
  cout << poisk (arr, buffer, 0, n-1) << endl;
}
}