I want to write a program to read a audio file and classify the various symbols into the number of times they occur , I was hoping i could use a switch statement and classify the 256 symblos but now i've learnt the standard ascii set is only from 0-127,so the rest of the symbols would vary from system to system?.

So how do i go on reading these symbols such that it would work on any system and also how can i access thier decimal values ??

I'm just hoping somebody points me in the right direction,Thankyou.

Open the file in binary mode, not text, then read each byte into an unsigned char, which has a value 0-255. If you want to count the number of occurrences all you need is an array of 255 and use the char as the index into the array

int counters[255] = {0}

ifstream in("myfile.bin", ios::binary);
unsigned char c;
while( in.read((char *)&c, 1) )
{
   counters[c]++;
}

Open the file in binary mode, not text, then read each byte into an unsigned char, which has a value 0-255. If you want to count the number of occurrences all you need is an array of 255 and use the char as the index into the array

int counters[255] = {0}

ifstream in("myfile.bin", ios::binary);
unsigned char c;
while( in.read((char *)&c, 1) )
{
   counters[c]++;
}

Thanks a lot,but i'm new to this and don't understand this part

while( in.read((char *)&c, 1) )

Why the use of a pointer and why reference &c ?

The first argument in.read requires is a pointer to a signed character buffer. The second is the length of that buffer.
char c;
But that is a signed buffer, which takes values in the range of -128...0...127 but you needed unsigned 0...255 so an unsigned char was used.
unsigned char c;

That is a character buffer with the length of one character.
To get the pointer one had to dereference the buffer.
&c
Which is the address of <c> which is what the function required.
Because the function needed a signed buffer it was then cast to
(char *)&c
Resulting int the
in.read( (char*) &c, 1 )

And the while loop stops reading on end-of-file.

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