Circular Buffer Read

Code

#include <stdio.h>

typedef struct {
    int buffer[10];
    int head;
    int tail;
    int count;
    int capacity;
} CircularBuffer;

void read_bytes(CircularBuffer *cb, int n) 
{
    while(n) //we should run this loop for n number of times definitely.
    {
        //Only thing is we can print elements count number of times.If count becomes <0 then we need to print NULL for all the remaining iterations.
      if(cb->count) 
      {
      printf("%d",cb->buffer[cb->tail]);
      cb->tail=(cb->tail+1)%(cb->capacity);
      (cb->count)--;
      }
      else 
       printf("NULL");
      n--;

      if(n)
        printf(" "); //extra space after printing an element also leads to mismatch in output.Hence we need to make sure no extra space is printed after last element.
    }
    printf("\nTail: %d",cb->tail);
}

int main() {
    CircularBuffer cb = {
        .buffer = {10, 20, 30, 40, 50, 60, 70, 80, 90, 100},
        .head = 3,
        .tail = 7,
        .count = 6,
        .capacity = 10
    };

    int n;
    scanf("%d", &n);
    read_bytes(&cb, n);

    return 0;
}

Solving Approach