C++ Program to display number of vowels, consonants, digits and white spaces in a string

Statement :
Program to display number of vowels, consonants, digits and white spaces in a string.
Code : 

// Program to display number of vowels, consonants, digits and white spaces in a string.

#include<iostream>

#include<string>

using namespace std;

void main()

{

           cout << "\tDisplay Number Of Vowels, Consonants, Digits And Spaces In A String\n\n";

              string str;

              int v=0, c=0, d=0, s=0;

cout << "Enter A Line Of String : ";

              getline(cin, str);

              for (int i = 0; i!='\0'; i++)

              {

                     if (str[i] == 'A' || str[i] == 'a' || str[i] == 'E' || str[i] == 'e' || str[i] == 'I' || str[i] == 'i' || str[i] == 'O' || str[i] == 'o' || str[i] == 'U' || str[i] == 'u')

                     {

                           v++;

                     }

                     else if ((str[i] >= 'A' && str[i] <= 'Z') || (str[i] >= 'a' && str[i] <= 'z'))

                     {

                           c++;

                     }

                     else if (str[i] == ' ')

                     {

                           s++;

                     }

                     else if (str[i] >= '0' && str[i] <= '9')

                     {

                           d++;

                     }

                     else

                     {

                           //other cahracters

                     }

              }

              cout << "Number Of Spaces : " << s << endl;

              cout << "Number Of Vowels : " << v << endl;

              cout << "Number Of Consonant : " << c << endl;

              cout << "Number Of Digits : " << d << endl;

       cout << "\n\n";

       system("pause");

}