优先队列解决哈夫曼编码问题

#include<iostream>
using namespace std;
class Heap {
private:
int *data, size;
public:
Heap(int length_input) {
data = new int[length_input];
size = 0;
}
~Heap() {
delete[] data;
}
void push(int value) {
data[size] = value;
int current = size;
int father = (current - 1) / 2;
while (data[current] < data[father]) {
swap(data[current], data[father]);
current = father;
father = (current - 1) / 2;
}
size++;
}
int top() {
return data[0];
}
void update(int pos, int n) {
int lchild = 2 * pos + 1, rchild = 2 * pos + 2;
int max_value = pos;
if (lchild < n && data[lchild] < data[max_value]) {
max_value = lchild;
}
if (rchild < n && data[rchild] < data[max_value]) {
max_value = rchild;
}
if (max_value != pos) {
swap(data[pos], data[max_value]);
update(max_value, n);
}
}
void pop() {
swap(data[0], data[size - 1]);
size--;
update(0, size);
}
int heap_size() {
return size;
}
};
int main()
{
int n,value,ans=0;
cin>>n;
Heap heap(n);
for(int i=1;i<=n;++i)
{
cin>>value;
heap.push(value);
}
if(n==1)
{
ans+=heap.top();
}
while(heap.heap_size()> 1)
{
int a=heap.top();
heap.pop();
int b=heap.top();
heap.pop();
ans=ans+a+b;
heap.push(a+b);
}
cout<<ans<<endl;
return 0;
}