I have this code which pops the highest priority node from the queue. Currently the highest priority is defined as 1. I would like to change this so the highest priority is from 10 -> 1. To clarify the problem is in the pop function, others are added simply for context.
Node and heap definitions:
struct intnode {
int value;
int priority;
};
typedef struct intnode IntNode;
struct heap {
IntNode *nodes;
int len;
int size;
};
typedef struct heap heap_t;
Here is the push function of the queue:
void push (heap_t *h, int priority, int value) {
if (h->len + 1 >= h->size) {
if(h->size) {
h->size = h->size * 2;
}
else {
h->size = 4;
}
h->nodes = (IntNode *)realloc(h->nodes, h->size * sizeof (IntNode));
}
int i = h->len + 1;
int j = i / 2;
while (i > 1 && h->nodes[j].priority > priority) {
h->nodes[i] = h->nodes[j];
i = j;
j = j / 2;
}
h->nodes[i].value = value;
h->nodes[i].priority = priority;
h->len++;
}
The pop function of the queue:
int pop (heap_t *h) {
int i, j, k;
if (!h->len) {
return -1;
}
int value = h->nodes[1].value;
h->nodes[1] = h->nodes[h->len];
h->len--;
i = 1;
while (1) {
k = i;
j = 2 * i;
if (j <= h->len && h->nodes[j].priority < h->nodes[k].priority) {
k = j;
}
if (j + 1 <= h->len && h->nodes[j + 1].priority < h->nodes[k].priority) {
k = j + 1;
}
if (k == i) {
break;
}
h->nodes[i] = h->nodes[k];
i = k;
}
h->nodes[i] = h->nodes[h->len + 1];
return value;
}
Thank you for your time!
