init

circularQueue.c

@@ -0,0 +1,93 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct {
+  int *keys;
+  int size;
+  int front;
+  int rear;
+
+} cq;
+
+cq *createqueue(int size) {
+  cq *q = (cq *)malloc(sizeof(cq));
+  q->size = size;
+  q->front = -1;
+  q->rear = -1;
+  q->keys = (int *)malloc(size * sizeof(int));
+  return q;
+}
+
+bool isFull(cq *q) { return ((q->rear + 1) % q->size == q->front); }
+bool isEmpty(cq *q) { return q->front == -1; }
+
+void enqueue(cq *q, int v) {
+  if (isFull(q)) {
+    printf("is full");
+  }
+  if (isEmpty(q)) {
+    q->front = 0;
+    q->rear = 0;
+  } else {
+    q->rear = (q->rear + 1) % q->size;
+  }
+  q->keys[q->rear] = v;
+}
+
+int dequeue(cq *q) {
+  if (isEmpty(q)) {
+    printf("Queue is empty! Cannot delete.\n");
+    return -1;
+  }
+  int v = q->keys[q->front];
+  if (q->front == q->rear) {
+    q->front = q->rear = -1;
+
+  } else {
+    q->front = (q->front + 1) % q->size;
+  }
+  return v;
+}
+
+void display(cq *q) {
+  if (isEmpty(q)) {
+    printf("Queue is empty!\n");
+    return;
+  }
+  int i = q->front;
+  while (1) {
+    printf("%d", q->keys[i]);
+    if (i == q->rear) {
+      break;
+    }
+    i = (i + 1) % q->size;
+  }
+}
+int main() {
+  int n;
+  printf("Enter size of queue: ");
+  scanf("%d", &n);
+
+  cq *q = createqueue(n);
+
+  enqueue(q, 10);
+  enqueue(q, 20);
+  enqueue(q, 30);
+  display(q);
+
+  dequeue(q);
+  display(q);
+
+  enqueue(q, 40);
+  enqueue(q, 50);
+  display(q);
+
+  dequeue(q);
+  display(q);
+
+  free(q->keys);
+  free(q);
+
+  return 0;
+}