From 7bdec49117001fc5ae4fda9515ca3bd39450aaa8 Mon Sep 17 00:00:00 2001
From: Eshika Khandelwal <71181616+esh04@users.noreply.github.com>
Date: Sat, 9 Oct 2021 21:42:31 +0530
Subject: [PATCH] Create priority_queue.c

added code for priority queues
---
 queue/priority_queue.c | 68 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 queue/priority_queue.c

diff --git a/queue/priority_queue.c b/queue/priority_queue.c
new file mode 100644
index 0000000..573826e
--- /dev/null
+++ b/queue/priority_queue.c
@@ -0,0 +1,68 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <assert.h>
+
+typedef long long int ll;
+//FIFO
+typedef struct qnode
+{
+    ll data;
+    ll priority;
+    struct qnode *next;
+} qnode;
+
+void initQ(qnode *first)
+{
+    first->data = 0;
+    first->priority = 0;
+    first->next = NULL;
+}
+void enqueue(qnode *p, ll a, ll b)
+{
+    qnode *temp = (qnode *)malloc(sizeof(qnode));
+    assert(temp);
+    temp->data = a;
+    temp->priority = b;
+    temp->next = NULL;
+    qnode *t = p;
+    while ((t->next != NULL) && ((t->next)->priority > b))
+    {
+        t = t->next;
+    }
+    temp->next = t->next;
+    t->next = temp;
+}
+ll dequeue(qnode *p)
+{
+
+    qnode *temp = p->next;
+    p->next = (p->next)->next;
+    ll r = temp->data;
+    free(temp);
+    return r;
+}
+void qdisplay(qnode *first)
+{
+    qnode *temp = first->next;
+    while (temp)
+    {
+        printf("%lld ", (temp->data));
+        temp = temp->next;
+    }
+
+    printf("\n");
+}
+int main()
+{
+    ll A[10] = {5, 3, 6, 7, 8, 1, 2, 4, 9, 0};
+    ll B[10] = {4, 6, 3, 2, 1, 8, 7, 5, 0, 9};
+    qnode *Q = (qnode *)malloc(sizeof(qnode));
+    initQ(Q);
+    for (ll i = 0; i < 10; i++)
+    {
+        enqueue(Q, A[i], B[i]);
+        //qdisplay(Q);
+    }
+    qdisplay(Q);
+}