UdpClient* Client::udpClientById(int udpClientId)
{
UdpClients::iterator i =
std::find_if(udpClients.begin(), udpClients.end(), compare_fun(&UdpClient::getId, udpClientId));
return (i != udpClients.end()) ? *i : 0;
}
mybtree* huffman_tree(frequency **f, int len, int (*compare_fun)(void*, void*))
{
// let f be a min heap
int i = 0;
mybtree **heap = (mybtree**)malloc(len * sizeof(mybtree*));
for(i = 0; i < len; i++)
heap[i] = mybtree_new(f[i]);
int son = 0;
int parent = 0;
mybtree *temp;
for(i = 0; i < len; i++){
son = i;
parent = (son - 1) / 2;
while(parent >= 0 && compare_fun(heap[son]->value, heap[parent]->value) < 0){
SWAP(heap[son], heap[parent], temp);
son = parent;
parent = (son - 1) / 2;
}
}
// get min 2 value and create a tree
// left 0, right 1, and right smaller than left
mybtree *root = heap[0];
frequency *fre;
son = 1;
parent = 0;
while(len > 1){
fre = (frequency*)malloc(sizeof(frequency));
fre->symbol = NULL;
fre->weight = 0;
root = mybtree_new(fre);
for(i = 0; i < 2; i++){
SWAP(heap[0], heap[len - 1], temp);
len--;
if(i == 0)
root->right = heap[len];
else
root->left = heap[len];
fre->weight += ((frequency*)heap[len]->value)->weight;
// re-heap
parent = 0;
son = parent * 2 + 1;
while(son < len){
if(son < len - 1 && compare_fun(heap[son]->value, heap[son + 1]->value) > 0)
son++;
if(compare_fun(heap[parent]->value, heap[son]->value) < 0)
break;
SWAP(heap[parent], heap[son], temp);
parent = son;
son = parent * 2 + 1;
}
}
heap[len] = root;
len++;
son = len - 1;
parent = (son - 1) / 2;
while(parent >= 0 && compare_fun(heap[son]->value, heap[parent]->value) < 0){
SWAP(heap[son], heap[parent], temp);
son = parent;
parent = (son - 1) / 2;
}
}
root = heap[0];
free(heap);
return root;
}
