Noob Q 2D array processing

[naildirt]

I am unable to check if the character in the 2D array isalpha

here is my code
#include<iostream>
#include<cctype>
#include<cassert>
#include<cstring>
const int maxChar = 20 ;
using namespace std ;
int main()
{
int count = 0 ;

char d[2][20] = { "hi" , "di" } ;


for(int r = 0 ; r < 2 ; r++)
{
cout << "loop1 " ;
for ( int c = 0 ; c != '\0' && c < 20 ; c++)
{

if (isalpha( d[r][c]))
{

cout << d[r][c] ;
}
else
cout << "nooooooo " ;



}
count++ ;

}
cout << "\n count is" << count ;

}