86. Circular Buffer Read

#include <stdio.h>

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

void read_bytes(CircularBuffer *cb, int n) {
    int rem = (cb -> count >= n) ? n : cb -> count;
    for (int i = 1; i <= rem; i++) {
        printf("%d", cb -> buffer[cb -> tail]);
        if (i < rem) printf(" ");
        cb -> tail = (cb -> tail + 1) % 10;
        cb -> count --;
        n--;
    }
    for (int i = 0; i < n; i++) {
        printf("%s", " NULL");
    }
    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;
}