[Kingroudy]

int i=0;
char str[500];
int strd[500];
ifstream b_file ( "example.txt" );
b_file>>str[0];
while (str[i]!='.')
{
switch (str[i])
{
       case 'a':
       case 'A':
       strd[i]=0;
       break;
// and here u go on and on and on for b and B, c and C...
}
       cout<<strd[i]<<' ';
       i++;
       b_file>>str[i];
       
}