add Chapter01 examples

Chapter01/ring_buffer.c

@@ -0,0 +1,50 @@
+#include <stdio.h>
+
+#define BUFFER_SIZE 5
+
+typedef struct {
+  int arr[BUFFER_SIZE]; // Array to store int values directly
+  size_t write_idx;     // Index of the next element to write (push)
+  size_t read_idx;      // Index of the next element to read (pop)
+  size_t count;         // Number of elements in the buffer
+} int_ring_buffer;
+
+void int_ring_buffer_init(int_ring_buffer *rb) {
+  rb->write_idx = 0;
+  rb->read_idx = 0;
+  rb->count = 0;
+}
+
+void int_ring_buffer_push(int_ring_buffer *rb, int value) {
+  rb->arr[rb->write_idx] = value;
+  rb->write_idx = (rb->write_idx + 1) % BUFFER_SIZE;
+  if (rb->count < BUFFER_SIZE) {
+    rb->count++;
+  } else {
+    // Buffer is full, move read_idx forward
+    rb->read_idx = (rb->read_idx + 1) % BUFFER_SIZE;
+  }
+}
+
+int int_ring_buffer_pop(int_ring_buffer *rb) {
+  if (rb->count == 0) {
+    return 0;
+  }
+  int value = rb->arr[rb->read_idx];
+  rb->read_idx = (rb->read_idx + 1) % BUFFER_SIZE;
+  rb->count--;
+  return value;
+}
+
+int main() {
+  int_ring_buffer rb;
+  int_ring_buffer_init(&rb);
+  for (int i = 0; i < 10; i++) {
+    int_ring_buffer_push(&rb, i);
+  }
+  while (rb.count > 0) {
+    int value = int_ring_buffer_pop(&rb);
+    printf("%d\n", value);
+  }
+  return 0;
+}