Question

I have an assignment based on the above stated problem. The sampling frequency and size per sample would be known in the problem. I just need an idea about the kind of coding that would be required for this.

Answer 1

The sampling frequency is irrelevant for this, but the size per sample (typically 8 or 16 bit per channel per sample) decides which pointer-size you need to use, so here the example of 8 bit per channel:

char* reader = begin; // interleaved
char* left = malloc(numsamples); // de-interleaved
char* right = malloc(numsamples);
while(reader<end) {
    *left = *reader;
    ++left;
    ++reader;
    *right = *reader;
    ++right;
    ++reader;
}

To do the same for 2 channel 16 bit interleaved audio you just declare all 3 buffers as short* and instead malloc(numsamples*2)