write a code to take a string as input and print no. of distinct alphabets in it.

#include <iostream>
#include <string>
using namespace std;

int main() {
  string str;
  cout << "Enter a string: ";
  getline(cin, str);
  int dist[26] = {0};
  for (int i = 0; i < str.length(); ++i) {
    if (str[i] >= 'a' && str[i] <= 'z') {
      dist[str[i] - 'a']++;
    }
  }
  int count = 0;
  for (int i = 0; i < 26; ++i) {
    if (dist[i] > 0) {
      count++;
    }
  }
  cout << "No. of distinct alphabets: " << count << endl;
  return 0;
}